研究者総覧

梶原 孝志 (カジワラ タカシ)

  • 研究院自然科学系化学領域 教授
  • 附属幼稚園 附属幼稚園長
Last Updated :2021/07/07

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学位

  • 博士(理学), 東北大学

研究キーワード

  • 錯体化学、磁気化学、希土類化学 

研究分野

  • ナノテク・材料, 無機・錯体化学

学歴

  • 東北大学 理学研究科

受賞

  • Best Poster Award, 43rd International Conference on Coordination Chemitry, K. Kobayashi, 2018年08月

論文

  • Anisotropy of Spin−Lattice Relaxations in Mononuclear Tb3+ Single-Molecule Magnets

    ACS Publications, 2020年, J. Phys. Chem., 124, 7930 - 7937

  • Correlation between Slow Magnetic Relaxations and Molecular Structures of Dy(III) Complexes with N5O4 Nona-Coordination

    梶原孝志

    2019年04月, Magnetochemistry, 5, 27, doi

  • A Holmium(III)-Based Single-Molecule Magnet with Pentagonal-Bipyramidal Geometry

    Takashi Kajiwara

    2017年, Angewandte Chemie - International Edition, 56 (38), 11306 - 11308, doi

    研究論文(学術雑誌)

  • Light Lanthanide Complexes with Crown Ether and Its Aza Derivative Which Show Slow Magnetic Relaxation Behaviors

    Hisami Wada; Sayaka Ooka; Tomoo Yamamura; Takashi Kajiwara

    Two sets of isostructural Ln(III) mononuclear complexes, [Ln(NO3)(3)(18-crown-6)] (Ln = Ce (1), Pr (2), and Nd (3)) and [Ln(NO3)(3)(1,10-diaza-18-crown-6)] (Ln = Ce (4), Pr (5), and Nd (6)), were synthesized, and their slow magnetic relaxation behavior was investigated. Since Ln(III) ions are located in an axially stressed ligand field in both sets of complexes, they can exhibit single-molecule magnet (SMM) behavior owing to the oblate-type electronic distributions of the ground sublevels found in Ce(III), Pr(III), and Nd(III). Field-induced slow magnetic relaxation was observed for Ce(III) and Nd(III) complexes 1, 3, 4, and 6 under an applied bias dc field of 1000 Oe, whereas no slow relaxation was observed for Pr(III) complexes 2 and 5. The slow magnetic relaxation behavior of 1, 3, 4, and 6 was correlated with the even-numbered J(z) sublevels of Ce(III) and Nd(III) ions, known as the Kramers system., 2017年01月, INORGANIC CHEMISTRY, 56 (1), 147 - 155, doi;web_of_science

    研究論文(学術雑誌)

  • Slow Magnetic Relaxation of Lanthanide(III) Complexes with a Helical Ligand

    梶原孝志

    2016年12月, Magnetochemistry, 2, 43, doi

  • One-dimensional Magnus-type platinum double salts

    Christopher H. Hendon; Aron Walsh; Norinobu Akiyama; Yosuke Konno; Takashi Kajiwara; Tasuku Ito; Hiroshi Kitagawa; Ken Sakai

    Interest in platinum-chain complexes arose from their unusual oxidation states and physical properties. Despite their compositional diversity, isolation of crystalline chains has remained challenging. Here we report a simple crystallization technique that yields a series of dimer-based 1D platinum chains. The colour of the Pt2+ compounds can be switched between yellow, orange and blue. Spontaneous oxidation in air is used to form black Pt2.33+ needles. The loss of one electron per double salt results in a metallic d(z2) state, as supported by quantum chemical calculations, and displays conductivity of 11 S cm(-1) at room temperature. This behaviour may open up a new avenue for controllable platinum chemistry., 2016年06月, NATURE COMMUNICATIONS, 7, 11950, doi;web_of_science

    研究論文(学術雑誌)

  • Structural switching from paramagnetic to single-molecule magnet behaviour of LnZn(2) trinuclear complexes

    Poh Ling Then; Chika Takehara; Yumiko Kataoka; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    Five LnZn(2) trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}(2)] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine; Ln = Tb 1, Dy 2, La 3, Tb0.14La0.86 4, and Dy0.21La0.79 5), were synthesised in which the Zn-II-Ln(III)-Zn-II array exhibits two slightly different arrangements: 1 and 2 exhibited slightly bent arrangements, whereas 3-5 exhibited more linear arrangements. These differences in the arrangements lead to a slightly different coordination geometry around Ln(III). From the detailed studies of dynamic susceptibility, 1 and 2 were found to be paramagnetic, whereas 4 and 5 were SMMs with barriers for the flipping of magnetisation with a height of 41.2(4) K and 156(4) K, respectively., 2015年, DALTON TRANSACTIONS, 44 (41), 18038 - 18048, doi;web_of_science

    研究論文(学術雑誌)

  • Slow magnetic relaxation of light lanthanide-based linear LnZn(2) trinuclear complexes

    Chika Takehara; Poh Ling Then; Yumiko Kataoka; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    Four isostructural LnZn(2) trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}(2)] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine), were synthesized, which include light lanthanide ions as spin carriers (Ln = Ce 1, Pr 2, Nd 3, and Sm 4). These complexes involve a linear Zn(II)-Ln(III)-Zn(II) array, which leads to an axially stressed ligand field and can also cause single-moleluce magnet (SMM) behavior in oblate-type electronic distributions of ground sublevels found in Ce(III), Pr(III), and Nd(III). Slow magnetic relaxation behavior was observed in 1 and 3 under an applied bias dc field of 1000 Oe, whereas such a slow relaxation was not observed in 2 and 4. The appearance of field-induced SMM behavior in 1 and 3 was correlated with the even-numbered J(z) sublevels of Ce(III) and Nd(III) ions known as the Kramers system., 2015年, DALTON TRANSACTIONS, 44 (41), 18276 - 18283, doi;web_of_science

    研究論文(学術雑誌)

  • Electron-Deficient Pt2M2Pt2 Hexanuclear Metal Strings (M = Pt, Pd) Supported by Triphosphine Ligands

    Eri Goto; Rowshan Ara Begum; Chiaki Ueno; Aya Hosokawa; Chie Yamamoto; Kanako Nakamae; Bunsho Kure; Takayuki Nakajima; Takashi Kajiwara; Tomoaki Tanase

    Electron-deficient Pt2M2Pt2 hexanuclear clusters, [Pt4M2(mu-dpmp)(4)(XylNC)(2)](PF6)(4) (M = Pt (7), Pd (8); dpmp = bis((diphenylphosphino)methyl)phenylphosphine), were synthesized by oxidation of hydride-bridged hexanuclear clusters [Pt4M2(mu-H)(mu-dpmp)(4)(XylNC)(2)](PF6)(3) (M = Pt (2), Pd (3)) and were revealed to involve a linearly ordered Pt2M2Pt2 array joined by delocalized bonding interactions with 84 cluster valence electrons, which are discussed on the basis of DFT calculations. The central MM distances of 7 and 8 are significantly reduced upon the apparent loss of a hydride unit from the MHM central part of 2 and 3, indicating that the bonding electrons in the adjacent MPt bonds migrate into the central MM bond to result in a dynamic structural change during two-electron oxidation of the hexanuclear metal strings. A similar Pt-6 complex terminated by two iodide anions, [Pt6I2(mu-dpmp)(4)](PF6)(2) (9), was synthesized from [Pt-6(mu-H)I-2(mu-dpmp)(4)](PF6) (5) by treatment with [Cp2Fe][PF6]. Complexes 7 and 8 were readily reacted with the neutral two-electron donors XylNC, CO, and phosphines to afford the trinuclear complexes [Pt2M(mu-dpmp)(2)(XylNC)L](PF6)(2) (M = Pt, L = XylNC (la), CO (10), PPh3 (11); M = Pd, L = XylNC (1b)) through cleavage of the electron-deficient central M-M bond. 'When complex 7 was reacted with the diphosphines (PP) trans-Ph2PCH=CHPPh2 (dppen) and Ph2P(CH2)(2)PPh2 (dppe), the diphosphine was inserted into the central M-M bond to afford [(XylNC)Pt-3(mu-dpmp)(2)(PP)Pt-3(mu-dpmp)(2)(XylNC)](PF6)(4) (12), which was transformed by treatment with another 1 equiv of diphosphine into the asymmetric trinuclear complexes [Pt-3(mu-dpmp)(2)(XylNC)(PP)](PF6)(2) (13). A further ligand exchange reaction of 13a (PP = trans-dppen) provided the diphosphine-terminated symmetrical Pt3 complex [Pt-3(mu-dpmp)(2)(L)(2)](PF6)(2) (L = trans-dppen (14a)). Complexes 7 and 8 were also reacted with [AuCl(PPh3)] to yield the Pt2MAu heterotetranuclear complexes [Pt2MAuCl(mu-dpmp)(2)(PPh3)(XylNC)RPF6)(2) (M = Pt (15), Pd (16)), in which the Pt2M trinuclear fragment is inserted into the Au-Cl bond in a 1,1-fashion on the central M atoms of the Pt2M2Pt2 string., 2014年04月, ORGANOMETALLICS, 33 (8), 1893 - 1904, doi;web_of_science

    研究論文(学術雑誌)

  • Magnetic relaxations in a Tb-based single molecule magnet studied by quasielastic neutron scattering

    Maiko Kofu; Takashi Kajiwara; Jason S. Gardner; Giovanna G. Simeoni; Madhusudan Tyagi; Antonio Faraone; Kenji Nakajima; Seiko Ohira-Kawamura; Motohiro Nakano; Osamu Yamamuro

    By using ac magnetic susceptibility and quasielatic neutron scattering (QENS) techniques, we have investigated a magnetization relaxation phenomenon of a rare-earth based single molecule magnet, TbCuC19H20N3O16. We clearly identified and characterized two magnetic relaxations. The slower relaxation observed in the ac susceptibility is at the ms timescale around T = 2 K and its activation energy is 16 K. On the other hand, the faster relaxation in the QENS measurements occurs on the timescale between ns and ps with activation energy of 174 K. The slower relaxation may occur through thermally activated tunneling among magnetic substates. We discuss two possible origins for the faster relaxation; one is a thermally activated tunneling between the higher excited states, the other is the magnetic relaxation coupled with the motion of ligands around the magnetic ions. This is the first clear observation of magnetic relaxation on the single molecule magnet revealed by QENS. (C) 2013 Elsevier B. V. All rights reserved., 2013年12月, CHEMICAL PHYSICS, 427, 147 - 152, doi;web_of_science

    研究論文(学術雑誌)

  • SMM Behavior Observed in Ce(III)Zn(II)(2) Linear Trinuclear Complex

    Shiori Hino; Moe Maeda; Yumiko Kataoka; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    The second example of the Ce(III)-based single-molecule magnet (SMM), which involves only one 4f electron as a spin carrier, was realized based on similar magnetostructural correlations with Tb(III)-based SMMs. The estimated energy barrier for spin flipping was Delta E/k(B) = 37(1)K, which is higher than that for the first Ce(III)-SMM, and slow magnetic relaxation was observed up to 15 K., 2013年10月, CHEMISTRY LETTERS, 42 (10), 1276 - 1278, doi;web_of_science

    研究論文(学術雑誌)

  • Hyperfine structure of magnetic excitations in a Tb-based single-molecule magnet studied by high-resolution neutron spectroscopy

    M. Kofu; O. Yamamuro; T. Kajiwara; Y. Yoshimura; M. Nakano; K. Nakajima; S. Ohira-Kawamura; T. Kikuchi; Y. Inamura

    We report inelastic neutron scattering results on a rare-earth-based single-molecule magnet, the Tb-Cu dinuclear complex. By means of a high-resolution neutron chopper spectrometer, the details of the excitations were clarified. The magnetic excitations are clearly observed at (h) over bar omega=1.7 and 12.3 meV. The transition energy of 1.7 meV corresponds to the energy barrier of magnetic relaxation estimated from an ac magnetic susceptibility measurement. This indicates that the magnetization reversal occurs through quantum tunneling between pairs of degenerated excited states at 1.7 meV, which is called a thermally activated tunneling process. Interestingly, these excitations exhibit further peak splitting in energy and their energies are independent of momentum transfer Q. Our calculation, which is based on a spin Hamiltonian, suggests that (i) the excitation at 1.7 meV originates from the exchange coupling between Tb3+ and Cu2+, (ii) the excitation at 12.3 meV corresponds to the transition between the multiplets J of the Tb3+ moment, and (iii) the fine peak splitting in energy is due to the hyperfine interaction between the nuclear spin and electron spin and orbital magnetic moments., 2013年08月, PHYSICAL REVIEW B, 88 (6), 064405, doi;web_of_science

    研究論文(学術雑誌)

  • A luminescent single-molecule magnet: Observation of magnetic anisotropy using emission as a probe

    Kei Yamashita; Rie Miyazaki; Yumiko Kataoka; Takayuki Nakanishi; Yasuchika Hasegawa; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    An assemblage of a Tb(iii) ion and two mononuclear [Zn< sup> II< /sup> (L)] complexes as antenna chromophores (H< inf> 2< /inf> L: Schiff base ligand) afforded a luminescent single-molecule magnet. The f-f emission spectrum had partially resolved fine structure which provides detailed information on the magnetic anisotropy of the < sup> 7< /sup> F< inf> 6< /inf> ground multiplet of the Tb(iii) ion. © The Royal Society of Chemistry 2013., 2013年02月14日, Dalton Transactions, 42 (6), 1987 - 1990, doi

    研究論文(学術雑誌)

  • Linear trinuclear Zn(II)-Ce(III)-Zn(II) complex which behaves as a single-molecule magnet

    Shiori Hino; Moe Maeda; Kei Yamashita; Yumiko Kataoka; Motohiro Nakano; Tomoo Yamamura; Hiroyuki Nojiri; Maiko Kofu; Osamu Yamamuro; Takashi Kajiwara

    Linear Zn(II)-Ce(III)-Zn(II) complex, which involves only one 4f electron as a spin source, behaves as an SMM. Easy-axis magnetic anisotropy for the ground F-2(5/2) state of Ce(III) was achieved by a uni-axial crystal field, which is formed with four phenoxo oxygens as axial donors with the other five oxygens as equatorial donors., 2013年, DALTON TRANSACTIONS, 42 (8), 2683 - 2686, doi;web_of_science

    研究論文(学術雑誌)

  • Wheel-Shaped Icosanuclear Homo- and Heterometallic Complexes of Ni-II, Co-II, and Cu-II Ions Supported by Unsymmetrical Aminoalcohol Ligands

    Takayuki Nakajima; Keiko Seto; Fumihiro Horikawa; Isao Shimizu; Andreas Scheurer; Bunsho Kure; Takashi Kajiwara; Tomoaki Tanase; Masahiro Mikuriya

    Reactions of M(OAc)(2)center dot 4H(2)O (M = Ni, Co) with 3-[benzyl(2-hydroxyethypamino]-1-propanol (H2L) in the presence of pyridine or triethylamine afforded novel homometallic icosanuclear wheel-shaped complexes [M20L4(HL)(4)(OAc)(28)] (M = Ni (1), Co (2)), which consist of a central M-12(II) single-stranded, nearly planar loop with four peripheral [M-2(HL)(OAc)(2)] fragments attached in an S-4 symmetrical fashion. The complexes can alternatively be recognized as saddle-shaped wheel structures, in which four tetranuclear units of [M4L(HL)(OAc)(2)](2-) are connected by four M2+ ions (M5). The tetranuclear unit itself can be derived from an ideal C-2 symmetrical [M-4(HL)(2)(mu-eta(2)-OAc)(4)(mu-eta(1),eta(1)-OAc)(2)(eta(1),eta(1)-OAc)](-) structure through deprotonation of the HL- ligand, and is composed of two plane shared M3O4 incomplete cubanes in which the M2 and M3 atoms are involved in the central fused plane and the M1 and M4 atoms are disposed at the apex sites. Mixed-metal icosanuclear complexes [NixM20-xL4(HL)(4)(OAc)(28)] (3, M = Co, x = 9.5) and [Ni12M8L4(HL)(4)(OAc)(28)] (4, M = Cu) were also synthesized by using equimolar amounts of Ni-II and ions, and were shown to have similar structures to 1 and 2. X-ray crystallographic and fluorescent analyses revealed that complex 3 contains nonstoichiometric amounts of Ni2+ and Co2+ ions in the ratio of 9.5:10.5 and that these are disordered at every metal site. In striking contrast, complex 4 has a stoichiometric formula of Ni12Cu8, which was confirmed by the Jahn-Teller elongation of Cu2+ ions, and consequently, the M2 and M5 positions are occupied exclusively by the Cu2+ ions. The temperature-dependent direct current (dc) magnetic susceptibility data showed the presence of ferromagnetic exchange interactions in the Ni homometallic (1) and NiCu bimetallic (4) complexes, while the Co homometallic (2) and NiCo bimetallic (3) complexes exhibited antiferromagnetic interactions due to spin-orbit coupling effects of the octahedral Co-II ions. The present results demonstrate that the unsymmetrical aminoalcohol ligand H2L is quite effective in organizing the homo- and heterometallic icosanuclear wheel-shaped metal arrangements., 2012年11月, INORGANIC CHEMISTRY, 51 (22), 12503 - 12510, doi;web_of_science

    研究論文(学術雑誌)

  • Correlation between slow magnetic relaxation and the coordination structures of a family of linear trinuclear Zn(II)-Ln(III)-Zn(II) complexes (Ln = Tb, Dy, Ho, Er, Tm and Yb)

    Moe Maeda; Shiori Hino; Kei Yamashita; Yumiko Kataoka; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    Six linear trinuclear [Ln{Zn(L)(AcO)}(2)]BPh4 complexes (H2L denotes the Schiff-base ligand formed by a condensation reaction between ethylenediamine and two equivalents of o-vanillin), including Ln = Tb (1), Dy (2), Ho (3), Er (4), Tm (5) and Yb (6) were synthesized and were confirmed to be isostructural via X-ray crystallographic analyses. The Ln(III) ion in each complex is deca-coordinated by four equatorial oxygen donors from the methoxo groups of the Schiff-base ligands, two oxygen donors from the acetate anions and four axial oxygen donors from the phenoxo groups of the Schiff-base ligands. AC susceptibility measurements, with an oscillating frequency of 10 to 10 000 Hz, revealed that 1, 2, 4 and 6 show slow magnetic relaxation under a 1000 Oe DC bias field, which occurs via a single process, as confirmed by the semi-circular Cole-Cole plots. These complexes are considered to be field-induced single-molecule magnets under these conditions. The presence or absence of the slow magnetic relaxation process is discussed by correlating the characteristic magnetic anisotropy of each Ln(III) ion with the ligand field anisotropy., 2012年, DALTON TRANSACTIONS, 41 (44), 13640 - 13648, doi;web_of_science

    研究論文(学術雑誌)

  • Magnetic Relaxation of Single-Molecule Magnets in an External Magnetic Field: An Ising Dimer of a Terbium(III)-Phthalocyaninate Triple-Decker Complex

    Keiichi Katoh; Takashi Kajiwara; Motohiro Nakano; Yasuhiro Nakazawa; Wolfgang Wernsdorfer; Naoto Ishikawa; Brian K. Breedlove; Masahiro Yamashita

    2011年, CHEMISTRY-A EUROPEAN JOURNAL, 17 (1), 117 - 122, doi;web_of_science

    研究論文(学術雑誌)

  • Structural Design of Easy-Axis Magnetic Anisotropy and Determination of Anisotropic Parameters of Ln(III)-Cu-II Single-Molecule Magnets

    Takashi Kajiwara; Motohiro Nakano; Kohei Takahashi; Shinya Takaishi; Masahiro Yamashita

    Four dinuclear Le(III)-Cu-II complexes with Ln = Tb (1), Dy (2), Ho (3), and Er (4) were synthesized to investigate the relationship between their respective magnetic anisotropies and ligand-field geometries. These complexes were crystallographically isostructural, and a uni-axial ligand field was achieved by using three phenoxo oxygen groups. Complexes 1 and 2 displayed typical single-molecule magnet (SMM) behaviors, of which the out-of-phase susceptibilities were observed in the temperature range of 1.8-5.0 K (1) and 1.8-20.0 K (2). The Cole-Cole plots exhibited a semicircular shape with alpha parameters in the range of 0.08-0.18 (2.6-4.0 K) and 0.07-0.24 (3.5-7.0 K). The energy barriers Delta/k(B) were estimated from the Arrhenius plots to be 32.9(4) K for 1 and 26.0(5) K for 2. Complex 3 displayed a slow magnetic relaxation below 3.0 K, whereas complex 4 did not show any frequency-dependent behavior for both in-phase and out-of-phase susceptibilities, which indicates that easy-axis anisotropy was absent. The temperature dependence of the dc susceptibilities for the field-aligned samples of 1-3 revealed that the chi T-M value continuously increased as the temperature was lowered, which indicates the presence of low-lying Stark sublevels with the highest vertical bar J(z)vertical bar values. In contrast, complex 4 displayed a smaller and temperature-independent chi T-M value, which also indicates that easy-axis anisotropy was absent. Simultaneous analyses were carried out for 1-3 to determine the magnetic anisotropy parameters on the basis of the Hamiltonian that considers B-2(0), B-4(0), and B-6(0)., 2011年, CHEMISTRY-A EUROPEAN JOURNAL, 17 (1), 196 - 205, doi;web_of_science

    研究論文(学術雑誌)

  • Wheel-Shaped (ErZn3II)-Zn-III Single-Molecule Magnet: A Macrocyclic Approach to Designing Magnetic Anisotropy

    Aika Yamashita; Akiko Watanabe; Shigehisa Akine; Tatsuya Nabeshima; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    2011年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 50 (17), 4016 - 4019, doi;web_of_science

    研究論文(学術雑誌)

  • Real time and space observation of domain wall migration in a MX-chain complex with a quasi-2D CDW state by using STM

    Shinya Takaishi; Hashen Wu; Takashi Kajiwara; Brian K. Breedlove; Hitoshi Miyasaka; Masahiro Yamashita

    In STM images of [Pd(chxn-d(4))(2)Br]Br-2, which is in a quasi-2D-CDW state, we observed domain wall migration due to fast soliton motion at neighboring chains to the domain wall., 2011年, DALTON TRANSACTIONS, 40 (10), 2160 - 2162, doi;web_of_science

    研究論文(学術雑誌)

  • Metal-organic frameworks with rare topologies: lonsdaleite-type metal formates and their magnetic properties

    Hyunuk Kim; Yinyong Sun; Yonghwi Kim; Takashi Kajiwara; Masahiro Yamashita; Kimoon Kim

    Single-crystal X-ray analysis revealed that isomorphous metal formates [M-6(HCOO)(12)]center dot DEF (M = Mg2+, Fe2+, Co2+, Zn2+) have a framework with the lonsdaleite net, which is one of the rare topologies in metal-organic frameworks; iron and cobalt formates with metal sites bridged by single atoms showed dominant ferromagnetic and antiferromagnetic interactions, respectively., 2011年, CRYSTENGCOMM, 13 (7), 2197 - 2200, doi;web_of_science

    研究論文(学術雑誌)

  • Magnetic properties of lanthanoid(III) phthalocyaninato triple-decker complexes in an external magnetic field and electronic transport properties for molecular spintronics

    K. Katoh; K. Yamamoto; T. Kajiwara; J. Takeya; B. K. Breedlove; M. Yamashita

    Lanthanoid phthalocyaninato complexes of Dy2(obPc)3 (1) and Tb2(obPc)3 (2) are shown to be a single-molecule magnet. The relationships among the magnetic relaxation properties of 1 in a direct current (dc) magnetic field in comparison to 2 and the electronic properties of a cast film are discussed., 2011年, Journal of Physics: Conference Series, 303 (1), 012035-012044, doi;scopus;scopus_citedby

    研究論文(国際会議プロシーディングス)

  • Multi-Path Magnetic Relaxation of Mono-Dysprosium(III) Single-Molecule Magnet with Extremely High Barrier

    Akiko Watanabe; Aika Yamashita; Motohiro Nakano; Tomoo Yamamura; Takashi Kajiwara

    2011年06月, CHEMISTRY-A EUROPEAN JOURNAL, 17 (27), 7428 - 7432, doi;web_of_science

    研究論文(学術雑誌)

  • Systematic Expansion of Supercubane Cores in Manganese Oxo Clusters with Tricarboxylate Ligands

    Yayoi Okui; Florina Aurelia Catusanu; Ryoko Kubota; Bunsho Kure; Takayuki Nakajima; Tomoaki Tanase; Takashi Kajiwara; Masahiro Mikuriya; Hitoshi Miyasaka; Masahiro Yamashita

    A novel class of high-nuclearity Mn-17 and Mn-19 mixed-valent complexes, [Mn-17(mu-O)(12)(mu-OMe)(2)(mu-kta)(6)(MeOH)(4)] (1), [Mn-17(mu-O)(14)(mu-kta)(6)L-4] [L = bpy (2a), phen (2b), 4,7-Ph(2)phen (2c), dmf (3)], and [Mn-19(mu-O)(14)(mu-kta)(6)(bpy)(6)]X-3 [X = PF6 (4a), BF4 (4b)], were synthesized by utilizing Kemp's tricarboxylate ligands (H(3)kta = cis,cis-1,3,5-trimethylcyclohexane-1,3,5- tricarboxylic acid). The complexes were characterized by X-ray crystallography and reveal mineralomimetic Mn-13 supercubane units, [Mn-13(mu-O)(14)], in which their oxidation states systematically altered, depending on their vertex face-capping ligands and Mn-II satellite fragments. Complex 2a was converted by treatment with benzoic acid and [Mn2O2(bpy)(4)](BF4)(3) to a cage-type Mn-14 complex, [Mn-14(mu-O)(12)(mu-OH)(6)(mu-Hkta)(6)(bpy)(6)](BF4)(4) (5), which show ferro- and antiferromagnetic interactions and slow magnetic relaxation at low temperature., 2011年10月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (28), 4325 - 4330, doi;web_of_science

    研究論文(学術雑誌)

  • Non-oxo 5-coordinate and 6-coordinate vanadium(IV) complexes with their precursor [LVIII(CH3OH)](0), where L = a trianionic aminetris(phenolate)-[N,O,O,O] donor ligand: a magnetostructural and EPR study

    Takashi Kajiwara; Rita Wagner; Eckhard Bill; Thomas Weyhermueller; Phalguni Chaudhuri

    Ligating properties of a tripodal, potentially tetradentate aminetris(phenol) ligand, tris(2-hydroxy-3,5-di-tert-butylbenzyl) amine, H3L, containing [N,O,O,O] donor atoms toward the vanadium ions in +III and IV oxidation states have been studied. The structures of complexes 1 [LVIII(CH3OH)](0), 2[LVIV(OCH3)](0) and 3[LVIV(acac)](0) were determined by X-ray diffraction methods as having five-coordinate V(III), 1, five-coordinate non-oxo-vanadium(IV), 2, and six-coordinate non-oxo-vanadium(IV) 3, respectively. Compounds 1-3 were also studied with electrochemical methods, variable-temperature (2-295 K) magnetic susceptibility measurements and X-band electron paramagnetic resonance (EPR) spectroscopy. The electrochemical results of 2 and 3 suggest metal-centered oxidation, i.e. the generation of a V-V-phenolate species. EPR investigations indicate a (d(xy))(1) ground state showing a considerable increase in the in-plane p-bonding, as is expected for a phenolate ligand., 2011年, DALTON TRANSACTIONS, 40 (47), 12719 - 12726, doi;web_of_science

    研究論文(学術雑誌)

  • Structural Study of Electronic States in Quasi-One-Dimensional Halogen-Bridged Mixed-Metal Complexes [Ni1-xPdx(chxn)(2)Br]Br-2

    Shinya Takaishi; Hashen Wu; Jimin Xie; Takashi Kajiwara; Brian K. Breedlove; Hitoshi Miyasaka; Masahiro Yamashita

    The electronic structures of quasi-one-dimensional halogen-bridged mixed-metal compounds [Ni1-xPdx(chxn)(2)Br]Br-2 were investigated by means of powder X-ray diffraction measurements. Unit cell lengths of all directions obeyed a linear relationship when x < 0.9, whereas those deviated when x > 0.9 especially in the case of the b and c axes. This deviation can be explained by a phase change from an M-III Mott-Hubbard state to an M-II-M-IV charge-density-wave state because of chemical pressure caused by the substitution of Pd ions into [Pd(chxn)(2)Br]Br-2 with smaller Ni ions., 2010年04月, INORGANIC CHEMISTRY, 49 (8), 3694 - 3696, doi;web_of_science

    研究論文(学術雑誌)

  • Single-Chain Magnets Constructed by Using the Strict Orthogonality of Easy-Planes: Use of Structural Flexibility to Control the Magnetic Properties

    Takashi Kajiwara; Hiroki Tanaka; Motohiro Nakano; Shinya Takaishi; Yasuhiro Nakazawa; Masahiro Yamashita

    A family of single-chain magnets (SCMs), of which the SCM character originated from the spatial arrangement of high spin Fell ions with easy-plane anisotropy, was synthesized, and their magnetic properties were investigated. The chain complexes including alternating high-spin Fell ions and low-spin Fe" ions, catena-Fell(C104)2{Felll(bpca)2}1C104 3MeNO2 (1.3MeNO(7)), catena-[Fell(C104)(H20){Feu(MeL)2}(CI04)2 2MeN04 H20 (2- 2MeNO2. H20), catena-Fell(C104)(H20){Fe(III)Bu ( L)2}i(uu 4)2.3.5MeNO2 (3- 3,5MeNO2), and catena-[{F ell (C104)(F120)F ell (H20)21 0.5{Fe"( L)211(C104)2.5.4EtNO2 (4.4EtNO2), were synthesized with the use of bridging ligand Hbpca (bis-(2-pyridylcarbonyl)amine)) and its derivatives of eel., HBI, and HPhL each incorporating methyl, tert-butyl, or phenyl group on the 4-position of pyridyl ring. These complexes showed a typical ferrimagnetic behavior on direct current (dc) susceptibility data, and from an alternating current (ac) susceptibility measurements, SCM or superparamagnetic behaviors were confirmed with the A/kB values of 22.5(4), 21.8(18), and 28.8(3) K for 1.3MeNO2, 2- 2MeNO2" H20, and 3 -3.5MeNO2, of which the easy-axis anisotropy was originated from the orthogonal arrangement of easy-planes of Fen ions. In the crystal structures, cylindrical voids were formed along the chain axis being surrounded by four chains in 1 -3MeNO2, 2 -2MeNO(2)- H(2)O, and 4 4EtNO(2) and two chains in 3 "3.5MeNO2, and solvent molecules as well as coordination-free perchlorate anions occupied these voids in a slightly different fashion depending on the complexes. 2.2MeNO2-1-120 maintains its chemical composition in a dried condition, whereas 1 "3MeNO2, 3 -3.5MeNO2, and 4 " 4EtNO2 easily release solvent molecules to give 1, 3, and 4, respectively. 1 and 3 maintain the crystalline character showing slightly different X-ray diffraction (XRD) patterns from those of 1 3MeNO2 and 3- 3.5MeNO2, and an enhancement of SCM character after release of the solvent molecules was observed for both. 4 lost crystalline character to become amorphous, and it lost the SCM character at the same time., 2010年09月, INORGANIC CHEMISTRY, 49 (18), 8358 - 8370, doi;web_of_science

    研究論文(学術雑誌)

  • Effect of an In-Plane Ligand on the Electronic Structures of Bromo-Bridged Nano-Wire Ni-Pd Mixed-Metal Complexes, [Ni1-xPdx(bn)(2)Br]Br-2 (bn=2S,3S-Diaminobutane)

    Mari Sasaki; Hashen Wu; Daisuke Kawakami; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Brian K. Breedlove; Masahiro Yamashita; Hideo Kishida; Hiroyuki Matsuzaki; Hiroshi Okamoto; Hisaaki Tanaka; Shinichi Kuroda

    Single crystals of quasi-one-dimensional bromo-bridged Ni-Pd mixed-metal complexes with 2S,3S-diaminobutane (bn) as an in-plane ligand, [Ni1-xPdx(bn)(2)Br]Br-2, were obtained by using an electrochemical oxidation method involving mixed methanol/2-propanol (1:1) solutions containing different ratios of [Ni-II(bn)(2)]Br-2 and [Pd-II(bn)(2)]Br-2. To investigate the competition between the electron-correlation of the Ni-III states, or Mott-Hubbard states (MH), and the electron-phonon interaction of the Pd-II-Pd-IV mixed valence states, or charge-density-wave states (CDW), in the Ni-Pd mixed-metal compounds, X-ray structure analyses, X-ray oscillation photograph, and Raman, IR, ESR, and single-crystal reflectance spectra were analyzed. In addition, the local electronic structures of Ni-Pd mixed-metal single crystals were directly investigated by using scanning tunneling microscopy (STM) at room temperature and ambient pressure. The oxidation states of [Ni1-xPdx(bn)(2)Br]Br-2 changed from a M-II-M-IV mixed valence state to a M-III MH state at a critical mixing ratio (x(c)) of similar to 0.8, which is lower than that of [Ni1-xPdx(chxn)(2)Br]Br-2 (chxn=1R,2R-diaminocyclohexane) (x(c) approximate to 0.9) reported previously. The lower value of x(c) for [Ni1-xPdx(bn)(2)Br]Br-2 can be explained by the difference in their CDW dimensionalities because the three-dimensional CDW ordering in [Pd(bn)(2)Br]Br-2 observed by using X-ray diffuse scattering stabilizes the Pd-II-Pd-IV mixed valence state more than two-dimensional CDW ordering in [Pd(chxn)(2)Br]Br-2 does, which has been reported previously., 2009年08月, INORGANIC CHEMISTRY, 48 (15), 7446 - 7451, doi;web_of_science

    研究論文(学術雑誌)

  • Direct observation of lanthanide(III)-phthalocyanine molecules on Au(111) by using scanning tunneling microscopy and scanning tunneling spectroscopy and thin-film field-effect transistor properties of Tb(III)- and Dy(III)-phthalocyanine molecules

    Keiichi Katoh; Yusuke Yoshida; Masahiro Yamashita; Hitoshi Miyasaka; Brian K. Breedlove; Takashi Kajiwara; Shinya Takaishi; Naoto Ishikawa; Hironari Isshiki; Feng Zhang Yan; Tadahiro Komeda; Masakazu Yamagishi; Jun Takeya

    The crystal structures of double-decker single molecule magnets (SMM) LnPc2 (Ln = Tb(III) and Dy(III); Pc = phthalocyanine) and non-SMM YPc2 were determined by using X-ray diffraction analysis. The compounds are isomorphous to each other. The compounds have metal centers (M ) Tb3+, Dy3+, and Y3+) sandwiched by two Pc ligands via eight isoindole-nitrogen atoms in a square-antiprism fashion. The twist angle between the two Pc ligands is 41.4°. Scanning tunneling microscopy was used to investigate the compounds adsorbed on a Au(111) surface, deposited by using the thermal evaporation in ultrahigh vacuum. Both MPc 2 with eight lobes and MPc with four lobes, which has lost one Pc ligand, were observed. In the scanning tunneling spectroscopy images of TbPc molecules at 4.8 K, a Kondo peak with a Kondo temperature (TK) of ∼250 K was observed near the Fermi level (V = 0 V). On the other hand, DyPc, YPc, and MPc2 exhibited no Kondo peak. To understand the observed Kondo effect, the energy splitting of sublevels in a crystal field should be taken into consideration. As the next step in our studies on the SMM/Kondo effect in Tb-Pc derivatives, we investigated the electronic transport properties of Ln-Pc molecules as the active layer in top- and bottom-contact thin-film organic field effect transistor devices. Tb-Pc molecule devices exhibit p-type semiconducting properties with a hole mobility (μH) of ∼10-4 cm2 V-1 s-1. Interestingly, the Dy-Pc based devices exhibited ambipolar semiconducting properties with an electron mobility (μe) of ∼10-5 and a μH of ∼10-4 cm2 V-1 s-1. This behavior has important implications for the electronic structure of the molecules. © 2009 American Chemical Society., 2009年07月29日, Journal of the American Chemical Society, 131 (29), 9967 - 9976, doi;pubmed;scopus;scopus_citedby

    研究論文(学術雑誌)

  • Electroconductive Porous Coordination Polymer Cu[Cu(pdt)(2)] Composed of Donor and Acceptor Building Units

    Shinya Takaishi; Miyuki Hosoda; Takashi Kajiwara; Hitoshi Miyasaka; Masahiro Yamashita; Yasuyuki Nakanishi; Yasutaka Kitagawa; Kizashi Yamaguchi; Atsushi Kobayashi; Hiroshi Kitagawa

    We synthesized a new porous coordination polymer Cu[Cu(pdt)(2)], which shows relatively high electrical conductivity (6 x 10(-4) S cm(-1) at 300 K) by the introduction of electron donors and acceptors as building units. This compound is applicable as a porous electrode with high power density. In addition, this compound forms a triangular spin lattice and shows spin frustration., 2009年10月, INORGANIC CHEMISTRY, 48 (19), 9048 - 9050, doi;web_of_science

    研究論文(学術雑誌)

  • One-step heterogeneous assembly of terbium(III) and silver(I) with thiacalix[4]arene ligands to form a cage including terbium(III) in an octa-oxygen cube

    Teppei Tanaka; Nobuhiko Iki; Takashi Kajiwara; Masahiro Yamashita; Hitoshi Hoshino

    A heterogeneous one-step self-assembly of Ag+, Tb3+, and thiacalix[4]arene (TCAS), of which the donor atoms S and O showed high selectivity toward Ag+ and Tb3+ ions, respectively, afforded a supramolecular cage compound, Ag-4(+)center dot Tb3+center dot TCAS(2), at the center of which an octa-oxygen cube encapsulated the Tb3+ center to completely shield it from solvent molecules., 2009年08月, JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY, 64 (3-4), 379 - 383, doi;web_of_science

    研究論文(学術雑誌)

  • Syntheses, Structures, and Magnetic Properties of Tetramanganese(III) and Hexamanganese(III) Complexes Containing Derivative of Biguanidate Ligand: Ferromagnetic Interaction via Imino Nitrogen

    Asako Igashira-Kamiyama; Takashi Kajiwara; Motohiro Nakano; Takumi Konno; Tasuku Ito

    The tetramanganese(III) and hexamanganese(III) complexes, [Mn-4(mu-pzbg)(2)(Hpzbg)(2)(MeO)(4)(MeOH)(H2O)]Cl-2 (1) and [Mn6O4(Hpzbg)(4)(AcO)(4)(MeO)(2)] (2), were synthesized by using a monopyrazolyl biguanide derivative (H(2)pzbg) as a multinucleating ligand, which was newly prepared by the nucleophilic addition of pyrazole to Dicyandiamide. Single-crystal X-ray analysis revealed that 2 possesses a face-sharing double cubane structure, in which six Mn(III) ions are bridged by six MeO- with four terminal kappa N-2-Hpzbg(-). On the other hand, 1 possesses an incomplete face-sharing double cubane structure in which four Mn(III) ions are bridged by four MeO- and two kappa N-2:kappa N-2-pzbg(2)-accompanied by two terminal kappa N-2-Hpzbg(-). In 1, both ferromagnetic and antiferromagnetic interactions occur between manganese(III) ions, of which the ferromagnetic one is assigned to be the interaction via the imino nitrogen atom, while all manganese(III) ions are connected in an antiferromagnetic manner in 2., 2009年12月, INORGANIC CHEMISTRY, 48 (23), 11388 - 11393, doi;web_of_science

    研究論文(学術雑誌)

  • Coordination enhancement of single-molecule magnet behavior of Tb(III)-Cu(II) dinuclear systems

    Takashi Kajiwara; Kohei Takahashi; Tomonari Hiraizumi; Shinya Takaishi; Masahiro Yamashita

    Tb(III)-Cu(II) based single-molecule magnets (SMMs) were synthesized to investigate the relationship between magnetic anisotropy and the symmetry of the ligand field, by the reaction of [TbCu(o-vanilate)(2)(NO(3))(3)] with 2,2-dimethyl-1,3-propanediamine (3), followed by the reaction of one another equivalent of o-vaniline (4). Both complexes behave as SMM in the temperature range of 2.8-4.0 K (3) and 2.8-5.2 K (4), showing semi-circle shapes of Cole-Cole plots with alpha parameters in the ranges of 0.27-0.41 and 0.11-0.32. The energy barriers Delta/k(B) for the spin flippings were estimated from the Arrhenius plots to be 29(2) K for 3 and 32.2(6) K for 4, respectively. (C) 2009 Elsevier Ltd. All rights reserved., 2009年06月, POLYHEDRON, 28 (9-10), 1860 - 1863, doi;web_of_science

    研究論文(学術雑誌)

  • Structural correlations between the crystal field and magnetic anisotropy of Ln-Cu single-molecule magnets

    Takashi Kajiwara; Kohei Takahashi; Tomonari Hiraizumi; Shinya Takaishi; Masahiro Yamashita

    Mixed ligand Ln(2)Cu(2) tetranuclear complexes, [{LnCu(L4)(L5)(NO(3))(2)}(2)] (L4(-) is a Schiff base ligand derived from o-vanilate, L5(2-) is a nitromethyl derivative of L4(-); Ln=Gd(4), Tb(5), and Dy(6)), were synthesized by reacting the corresponding dinuclear complexes [LnCu(o-vanilate)(2)(NO(3))(3)] with ethylamine in a nitromethane solution. From detailed studies of magnetic anisotropies 5 was shown to behave as an SMM, whereas 6 was not an SMM., 2009年, CRYSTENGCOMM, 11 (10), 2110 - 2116, doi;web_of_science

    研究論文(学術雑誌)

  • Structures and Magnetic Properties of Dinuclear Copper(II) Complexes Containing a Bulky Diamine Ligand, 1,2-Dipiperidinoethane

    Machiko Arakawa-Itoh; Kana Tokuman; Yukie Mori; Takashi Kajiwara; Masahiro Yamashita; Yutaka Fukuda

    A reaction of copper(II) perchlorate with a sterically hindered diamine, 1,2-dipiperidinoethane (dipe), yields two dinuclear complexes: di-mu-hydroxo dinuclear complex [{Cu(ClO4)(dipe)(mu-OH)}(2)] (1) and di-mu-alkoxo dinuclear complex [{Cu(ClO4)(dipe-O)}(2)] (2) (dipe-O- is 1-(2-piperidinoethyl)piperidin-3-olate which was newly obtained in this work). The structures of complexes 1 and 2 were confirmed by X-ray crystallography. Complex 2 is meso form containing (R)- and (S)-dipe-O-. Dipe-O- acts as a tridentate ligand with an N,N,O-donor set and bridges two copper(II) ions through the oxygen atom. The oxygen atom is incorporated into dipe from atmospheric molecular oxygen during the reaction of dipe with copper ion. The temperature dependences of chi T-m values were different between 1 and 2 depending on the bridging structures. Complex 1 shows ferromagnetic interaction and the value of 2J = 117cm(-1) is in agreement with that predicted from the angle Cu-O-Cu bridging angle of 96.9 degrees. Complex 2, the bridging angle of which is 100.59 degrees, shows a strong antiferromagnetic interaction (-2J > 400cm(-1)). The singlet-triplet energy gap for complex 2 was estimated from DFT calculation., 2009年03月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 82 (3), 358 - 363, doi;web_of_science

    研究論文(学術雑誌)

  • A Low-Temperature Scanning Tunneling Microscope Investigation of a Nonplanar Dysprosium-Phthalocyanine Adsorption on Au(111)

    Yan-Feng Zhang; Hironari Isshiki; Keiichi Katoh; Yusuke Yoshida; Masahiro Yamashita; Hitoshi Miyasaka; Brian K. Breedlove; Takashi Kajiwara; Shinya Takaishi; Tadahiro Komeda

    Self-assemblies of a nonplanar dysprosium-phthalocyanine (DyPc) molecule on the reconstructed Au(111) substrate have been examined with a low-temperature scanning tunneling microscope (STM). A four-lobed structure with a dark center hole is imaged as an isolated DyPc molecule, where the Dy atom is expected to be positioned below the Pc plane and bound,to the Au substrate. Careful measurements reveal that the axes of isolated DyPc molecules align well with the high symmetry directions of Au. This fact illustrates a strong molecule-substrate interaction. In a monolayer film, a square molecule lattice is observed, where the geometries of the molecules can be determined by our submolecularly resolved STM images. The deduced lattice vectors and the azimuthal angles of the molecules account for a dominant molecule-molecule interaction. In a bilayer growth regime, the bonding configurations of the molecules in the second layer coincide with that of the first layer. A similar azimuthal angle appearing in the two layers may indicate a columnar packing geometry of DyPc molecules., 2009年08月, JOURNAL OF PHYSICAL CHEMISTRY C, 113 (32), 14407 - 14410, doi;web_of_science

    研究論文(学術雑誌)

  • Low-Temperature Scanning Tunneling Microscopy Investigation of Bis(phthalocyaninato)yttrium Growth on Au(111): From Individual Molecules to Two-Dimensional Domains

    Yan Feng Zhang; Hironari Isshiki; Keiichi Katoh; Yusuke Yoshida; Masahiro Yamashita; Hitoshi Miyasaka; Brian K. Breedlove; Takashi Kajiwara; Shinya Takaishi; Tadahiro Komeda

    We show a 4.8 K STM observation of a double-decker bis(phthalocyaninato)yttrium (YPc(2); Pc = phthalocyanine) molecule adsorption on Au(111) substrate. An eight-lobed structure was imaged as the submolecule STM contrast of a single molecule both in an isolated state and in a molecule film. This feature arises from the top Pc group, where both sides of the four phenyl rings are highlighted. As an isolated molecule, the adsorption orientation is determined by the lower Pc, the diagonal axis of which aligns parallel to the close-packed direction of Au(111). In a 2D film, a near-square molecule lattice appears with a unit of similar to 1.47 x 1.38 nm(2), and one of the lattice vectors is rotated by similar to 15 degrees from the close-packed direction. A tentative model is provided to illustrate the molecule array where neighboring molecules are rotated by similar to 30 degrees from each other. In this way, the lower Pcs should align along the [10 (1) over bar] and [(2) over bar 11] directions (or their equivalent directions) alternately. All these facts illustrate the molecule-substrate and the molecule-molecule interactions in the initial adsorption and in the film accumulation., 2009年06月, JOURNAL OF PHYSICAL CHEMISTRY C, 113 (22), 9826 - 9830, doi;web_of_science

    研究論文(学術雑誌)

  • Direct Synthesis and Crystal Structure of Dehydrated State in Vapochromic MMX-type Quasi-One-Dimensional Iodide-Bridged Platinum Complexes

    Hiroaki Iguchi; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Masahiro Yamashita; Hiroyuki Matsuzaki; Hiroshi Okamoto

    The dehydrated vapochromic 1D coordination polymer, (H(3)NC(4)H(8)NH(3))(2)[Pt(2)(pop)(4)I] (1) was synthesized directly from methanol solution. Although vapochromic 1 center dot A 4H (2) O has been synthesized, dehydrated high-temperature structure has never been determined because of lowering the quality of crystal by dehydration. The crystal structure of 1 was determined by X-ray crystal structure analysis, and we confirmed that it was identical to the dehydrated high-temperature structure of 1 center dot A 4H (2) O by comparing the powder X-ray diffraction (XRD) patterns. The Pt-I-Pt distance (d(Pt-I-Pt)) of compound 1 center dot A 4H (2) O was shortened for approximately 1.1 A... by desorption of water to form compound 1, accompanied with phase transition in electronic states. The other crystal including methanol molecule as lattice solvent, 1 center dot A 2MeOH, was also obtained as by-product. The synthesis from various kinds of organic solvent has the great potential to develop the field of vapochromism accompanying phase transition of electronic state., 2009年03月, JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS, 19 (1), 85 - 90, doi;web_of_science

    研究論文(学術雑誌)

  • Highly Luminescent Superparamagnetic Diterbium(III) Complex Based on the Bifunctionality of p-tert-Butylsulfonylcalix[4]arene

    Takashi Kajiwara; Miki Hasegawa; Ayumi Ishii; Kensuke Katagiri; Munkhtsetseg Baatar; Shinya Takaishi; Nobuhiko Iki; Masahiro Yamashita

    A diterbium(III) complex was synthesized by using p-tert-butylsulfonylcalix[4]arene, which adopts a 1,2-alternate conformation, acts as a sensitive optical-antenna chromophore for UV and near-UV light and causes easy-axis magnetic anisotropy in the Tb(III) ions. The complex showed efficient If emission with a corrected quantum yield of ca. 85% even at room temperature. In addition, it showed superparamagnetic behaviour due to slow magnetic relaxation at low temperatures. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008), 2008年12月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (36), 5565 - 5568, doi;web_of_science

    研究論文(学術雑誌)

  • Coordination-Tuned Single-Molecule-Magnet Behavior of Tb(III)-Cu(II) Dinuclear Systems

    梶原孝志

    2008年, Inorg. Chem., 47, 8604 - 8606

  • Charge-density-wave to Mott-Hubbard phase transition in quasi-one-dimensional bromo-bridged Pd compounds

    Shinya Takaishi; Mitsuhito Takamura; Takashi Kajiwara; Hitoshi Miyasaka; Masahiro Yamashita; Muneaki Lwata; Hiroyuki Matsuzaki; Hiroshi Okamoto; Hisaaki Tanaka; Shin-ichi Kuroda; Hiroyuki Nishikawa; Hiroki Oshio; Kenichi Kato; Masaki Takata

    A-Pd-III-Br-Pd-III-Mott-Hubbard state was observed in a quasi-one-dimensional bromo-bridged Pd compound [Pd(en)(2)Br](C-5-Y)(2)center dot H2O (en = ethylenediamine, C-5-Y = dipentylsulfosuccinate) for the first time. The phase transition between Mott-Hubbard and charge-density-wave states occurred at 206 +/- 2 K and was confirmed by using X-ray, ESR, Raman and electronic spectroscopies, electrical resistivity, and heat capacity. From X-ray powder diffraction patterns and Raman spectra of a series of Pd-Br compounds, [Pd(en)(2)Br](C-n-Y)(2)center dot H2O (n = 4, 5, 6, 7, 8, 9, and 12), chemical pressure from the alkyl chains of the counterions caused the phase transition., 2008年09月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 130 (36), 12080 - 12084, doi;web_of_science

    研究論文(学術雑誌)

  • Three-dimensionally ordered CDW state in quasi-one-dimensional iodo-bridged dinuclear platinum mixed-valence compounds, A(4)[Pt2I(POP)(4)]center dot nH(2)O (A = aromatic ammonium cations)

    Satoshi Matsunaga; Kouichi Takizawa; Daisuke Kawakami; Hiroaki Iguchi; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Masahiro Yamashita; Hiroyuki Matsuzaki; Hiroshi Okamoto

    Linear-chain iodo-bridged dinuclear Pt mixed-valence compounds with aromatic ammonium countercations, A(4)[Pt2I(POP)(4)]center dot nH(2)O [POP = P2O5H22-, A = benzyl ammonium (n = 2; 1), anilinium (n = 2; 2), and p-methoxy anilinium (n = 2; 3)], that have three-dimensionally ordered structures were synthesized. In the case of 1-3 the aromatic ammonium countercations were located between neighboring Pt chains and stacked in 1D columns. pi-pi Interactions between the phenyl rings and hydrogen bonds between the -NH3+ moieties and the oxygen atoms of the pop ligand link the Pt chains together, thus giving rise to a three-dimensionally ordered CDW state. This is the first observation of this phenomenon in compounds of this type. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)., 2008年07月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (21), 3269 - 3273, doi;web_of_science

    研究論文(学術雑誌)

  • Hybridized complexes of [MnIII2] single-molecule magnets and Ni dithiolate complexes

    梶原孝志

    2008年, Inorg. Chim. Acta, 361, 3863-3273

  • Synthesis of a sulfur-bridged diphosphine ligand and its unique complexation properties toward palladium(II) ion

    Naoya Morohashi; Yuki Akahira; Shinya Tanaka; Kensuke Nishiyama; Takashi Kajiwara; Tetsutaro Hattori

    Sulfur-bridged phenol dimer 3(2) is converted into P-S-P ligand 5, mono- and dinuclear palladium complexes of which are selectively synthesized and characterized by X-ray crystallography., 2008年04月, CHEMISTRY LETTERS, 37 (4), 418 - 419, doi;web_of_science

    研究論文(学術雑誌)

  • Why does the disorder of R-pn and rac-pn ligands in the quasi-one-dimensional bromo-bridged Ni-III complexes, [Ni(pn)(2)Br]Br-2 (pn=1,2-diaminopropane) afford similar STM patterns?

    Hashen Wu; Daisuke Kawakami; Mari Sasaki; Jimin Xie; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Masahiro Yamashita; Hiroyuki Matsuzaki; Hiroshi Okamoto

    The disordered patterns of R- and rac-1,2-diaminopropane (pn) in quasi-one-dimensional bromo-bridged Ni(III) complexes, [Ni-III(pn)(2)Br]Br-2, have been investigated by single-crystal X-ray structure determination and scanning tunneling microscopy (STM). X-ray structure determination shows that the methyl moieties are disordered on the right- and left-hand sides with half occupancies in both compounds, while the carbon atoms of the ethylene moieties of pn ligands are disordered in [Ni(rac-pn)(2)Br]Br-2 and not disordered in [Ni(R-pn)(2)Br]Br-2. In the STM images of both compounds, the bright spots are not straight but fluctuated with the similar patterns. We have concluded that tunnel current from the STM tip to metal ions are detected via methyl groups of pn ligands., 2007年09月, INORGANIC CHEMISTRY, 46 (18), 7410 - 7413, doi;web_of_science

    研究論文(学術雑誌)

  • Synthesis, structure, and magnetic property of a new Fe(II)-Fe(III) alternating single-chain magnet constructed with a methyl-substituted bpca– ligand

    梶原孝志

    A new Fe(II)-Fe(III) alternating single chain magnet, catena-[Fe-II(ClO4)(H2O){Fe-III(bmpca)(2)}](ClO4)(2), was synthesized using methyl-substituted bpca(-) ligand, bmpca(-) (Hbpca and Hbmpca denote bis(2-pyridylcarbonyl)amine and bis(4-methyl-2-pyridylcarbonyl)amine, respectively). The one-dimensional complex shows the ferrimangetic behavior and frequency dependent out-of-phase ac susceptibility X ''(m), with the alpha parameter of 0.25 estimated by the semicircle Cole-Cole plot. The activation energy Delta was estimated to be 19(1) K from an Arrhenius plot. (c) 2006 Elsevier Ltd. All rights reserved., 2007年06月, POLYHEDRON, 26 (9-11), 2105 - 2109, doi;web_of_science

    研究論文(学術雑誌)

  • Tetra- and di-nuclear copper(II) complexes with stereoisomers of sulfinylcalix[4]arene arising from the disposition of four S=O groups

    Nobuhiko Iki; Yusuke Yamane; Naoya Morohashi; Takashi Kajiwara; Tasuku Ito; Sotaro Miyano

    A systematic investigation was conducted on the structures of tetra- and di-nuclear copper(II) complexes with three stereoisomers of sulfinylcalix[4]arenes (H4L), the isomerism of which is determined by the disposition of the sulfinyl oxygen with respect to a reference oxygen from the mean plane containing four sulfur atoms. The sulfinylcalix[4]arene with a trans-cis-trans S = O orientation (H4Lrtct) reacted with Cu(OAc)(2) to form [Cu(II)4(L-rtct)(OAc)(3)(mu-MeO)(MeOH)] (1), in which Lrtct4- adopts a cone conformation to afford tetrakis fac-tridentate coordination through four phenoxo oxygens and four sulfinyl groups giving a square Cu-4(II) core. Ligands H4Lrccc and H4Lrctt having cis-cis-cis and cis-trans-trans configurations formed [Cu-4(II)(L-rccc)(OAc)(3)(mu-OH)] (2) and [Cu-4(II)(L-rctt)(OAC)(3)(mu-OH)] (3), respectively, which have common features, such as a cone-type conformation of L4-, tetrakis fac-tridentate coordination fashion, and tetra-copper(II) core in a square-pyramidal geometry. The similarities among 1-3 clearly show that sulfinylcalix[4]arenes can coordinate to Cu-II in a fac-tridentate fashion via a donor atom X (O or S) from a sulfinyl group and two flanking phenoxo O-s(-) and that X is simply determined by the X-Cu distance. Using [Cu(acac)(2)] as a copper(II) source, H4L(rctt) formed [Cu-2(II)(H2Lrctt)(2)] (4), suggesting the significance of auxiliary ligand for bridging copper(II) centers to assemble the core, that is, the acetato ligands in complexes 1-3 are needed to form the core structure. Metal-metal interactions were investigated by means of magnetic susceptibility, and it was found that both ferro- and antiferromagnetic interactions occur in tetracopper(II) complex 3. In contrast, antiferromagnetic interaction is present in dicopper(II) complex 4., 2007年06月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 80 (6), 1132 - 1139, doi;web_of_science

    研究論文(学術雑誌)

  • Direct observation of the ground-spin alignment of Fe(II)-Fe(III) single-chain magnet by muon-spin relaxation

    Takashi Kajiwara; Isao Watanabe; Yukihiro Kaneko; Shinya Takaishi; Masaya Enomoto; Norimichi Kojima; Masahiro Yamashita

    Zero field and longitudinal field muon-spin relaxation measurements were carried out for the single-chain magnet catena -[Fe-II(ClO4)(2){Fe-III(bpca)(2)}]ClO4, to reveal the growth of short-range spin ordering in the zero-external magnetic field below 6 K., 2007年10月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 129 (41), 12360 - +, doi;web_of_science

    研究論文(学術雑誌)

  • Hybrid molecular material exhibiting single-molecule magnet behavior and molecular conductivity

    Hiroki Hiraga; Hitoshi Miyasaka; Kazuya Nakata; Takashi Kajiwara; Shinya Takaishi; Yugo Oshima; Hiroyuki Nojiri; Masahiro Yamashita

    Two unique materials based on Mn-4 single-molecule magnet (SMM) clusters (S-T = 9) and integer or non-integer average valent platinum maleonitriledithiolate (mnt(2-)) complexes, [{(Mn2Mn2III)-Mn-II(hmp)(6)(MeCN)(2)},{Pt(mnt)(2)}(2)][Pt(mnt)(2)](2)center dot 2MeCN (1) and [{(Mn2Mn2III)-Mn-II(hMP)(6)(MeCN)(2)},{Pt(mnt)(2)}(4)][Pt(mnt)(2)](2) (2), were synthesized by the material diffusion method and electrochemical oxidation, respectively (hmp(-) = 2-hydroxymethylpyridinate). 1 and 2 are comprised of four and six [Pt(mnt)(2)](n-) units, respectively, in addition to a common (Mn2Mn2III)-Mn-II double-cuboidal unit, [Mn-2(II)-Mn (III)(2)(hmP)(6)(MeCN)(2)](4+) (hereinafter [Mn-4](4+)). Among the [Pt(mnt)(2)](n-) units, two units in 1 and four units in 2 are coordinated with the [Mn-4](4+) unit, forming a 1D chain of {-[Mn-4]-[Pt(mnt)(2)](2)-} for 1 and a discrete subunit of [Pt(mnt)(2)](2)-[Mn-4]-[Pt(mnt)(2)](2)} for 2. The other two [Pt(mnt)(2)](n-) units, occupying void space of the packing, form a stacking column with the coordinating [Pt(mnt)(2)](n-) units, finally constructing hybrid frames of aggregates consisting of [Mn-4](4+) units and [Pt(mnt)(2)](n-) units. Electronic conductivity measurements revealed that 1 is an insulator and 2 is a semiconductor with sigma = 0.22 S center dot cm(-1),at room temperature and an activation energy of 136 meV. Detailed magnetic measurements proved that the [Mn-4](4+) units in 1 and 2 behave as SMMs with an S-T = 9 ground state at low temperatures. There is no significant interaction between [Mn-4](4+) units and [Pt(mnt)(2)](n-) units, but interactions between localized spins of [Pt(mnt)(2)](n-) were detected even in 2 at low temperatures where the conductivity is electronically insulated. 2 is the first example of a hybridized material exhibiting SMM behavior and electronic conductivity., 2007年11月, INORGANIC CHEMISTRY, 46 (23), 9661 - 9671, web_of_science

    研究論文(学術雑誌)

  • Metal-insulator transition of charge-transfer salts based on unsymmetrical donor DMET and metal halide anions (DMET)(4)(MCl4)(TCE)(2) (M = Mn, Co, Cu, Zn; TCE=1,1,2-trichloroethane)

    Hiroshi Ito; Daichi Suzuki; Harutaka Watanabe; Hisaaki Tanaka; Shin-ichi Kuroda; Masamichi Umemiya; Norihito Kobayashi; Makoto Goto; Ken-ichi Sugiura; Hitoshi Miyasaka; Shinya Takaishi; Takashi Kajiwara; Masahiro Yamashita; Eiji Ohmichi; Toshihito Osada

    New charge-transfer salts based on an unsymmetrical donor DMET [dimethyl(ethylenedithio)diselenadithiafulvalene] and metal halide anions (DMET)(4)(MCl4)-Cl-II(TCE)(2) (M = Mn, Co, Cu, Zn; TCE = 1,1,2-trichloroethane) have been synthesized and characterized by transport and magnetic measurements. The crystal structures of the DMET salts are isostructural, consisting of a quasi-one-dimensional stack of DMET and insulating layers containing metal halide anions and TCE. Semimetallic band structures are calculated by the tight-binding approximation. Metal-insulator transitions are observed at T-MI = 25, 15, 5-20, and 13 K for M = Mn, Co, Cu, and Zn, respectively. The M = Cu salt exhibits anisotropic conduction at ambient pressure, being semiconducting in the intralayer current direction but metallic for the interplane current direction, down to T-MI. The metal-insulator transitions are suppressed under pressure. In the M = Co and Zn salts, large magnetoresistances with hysteresis are observed at low temperatures, on which Shubnikov-de Haas oscillations are superposed above 30 T. In the M = Cu salt, no hysteresis is observed but clear Shubnikov-de Haas oscillations are observed. The magnetoresistance is small and monotonic in the M = Mn salt. Paramagnetic susceptibilities of the spins of the magnetic ions are observed for the M = Mn, Co, and Cu salts with small negative Weiss temperatures of similar to 1 K. In the nonmagnetic M = Zn salt, Pauli-like pi-electron susceptibility that vanishes at T-MI is observed. The ground state of the pi-electron system is understood as being a spin density wave state caused by imperfect nesting of the Fermi surfaces. In this pi-electron system, the magnetic ions of the M = Mn, Co, and Cu salts interact differently, exhibiting a variety of transport behaviors., 2007年07月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 129 (27), 8510 - 8518, doi;web_of_science

    研究論文(学術雑誌)

  • Tuning of electronic structures of quasi-one-dimensional bromo-bridged Pd-II-Pd-IV mixed-valence complexes by substituting counter anions

    Hisamitsu Arakawa; Daisuke Kawakami; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Ken-ichi Sugiura; Masahiro Yamashita; Hideo Kishida; Hiroshi Okamoto

    New quasi-one-dimensional bromo-bridged Pd-II-Pd-IV mixed-valence complexes with long chain alkylsufonates [Pd(en)(2)][PdBr2(en)](CnH2n+1SO3)(4)center dot 2H(2)O (en = ethylenediamine, n = 7, 8, 9, and 10) were synthesized. With increasing alkyl-chain length (n) of the counter anions, the (PdPdIV)-Pd-center dot center dot center dot distances decreased, indicating that the oxidation states of the Pd atoms are close to the Pd-III state., 2007年01月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 80 (1), 189 - 191, web_of_science

    研究論文(学術雑誌)

  • A nickel(II) gold(I) D-penicillaminate coordination system with multiple switching in color, magnetism, and chirality

    Mai Taguchi; Asako Igashira-Kamiyama; Takashi Kajiwara; Takumi Konno

    2007年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 46 (14), 2422 - 2425, doi;web_of_science

    研究論文(学術雑誌)

  • Spin coupling in the supramolecular structure of a new tetra(quinoline-TEMPO)yttrium(III) complex

    Luca Maretti; Marilena Ferbinteanu; Fanica Cimpoesu; Saiful S. M. Islam; Yasunori Ohba; Takashi Kajiwara; Masahiro Yamashita; Seigo Yamauchi

    The newly synthesized tetra(quinoline-TEMPO)yttrium(III) potassium salt shows interesting structural features at the molecular and supramolecular levels, revealed by the analysis of the X-ray diffraction data. The magnetic susceptibility and EPR data corroborated with structural considerations showed that the exchange and dipolar spin coupling interactions are taking place at the nodes assembling the supramolecular 2D structure. The Y(III) center shows antiprismatic octacoordination, close to the idealized D-2 symmetry. The diamagnetic transition metal plays no role in mediating the radical interactions since the TEMPO-type fragments are remote from the chelating moieties of the ligand. In turn, significant interaction occurs on the nodes consisting in the quasi-rectangular coordination of potassium counterions by the spin-bearing TEMPO groups coming from four distinct complex units. The antiferromagnetic susceptibility was consistently modeled by a spin Hamiltonian based on the rectangle topology of four spins S = (1)/(2). The fitted exchange parameters are J(a) = -5.1 cm(-1) and J(b) = -3.4 cm(-1) for the edges, imposing J(d) = 0 for the diagonal. These values are in excellent agreement with the ab initio results J(a) = -4.83 cm(-1), J(b) = -3.44 cm(-1), J(d) = -0.07 cm(-1) obtained in a CASSCF(12,8) calculation. Based on the reliability of the ab initio results we were able to select the presented J parameters among several versions of multiple solutions with acceptable goodness of the fit. A methodological caveat about the artifacts of the automatic use of best fit parameters, in the absence of supplementary criteria, in the context of relative blindness of magnetic susceptibility modeling, is raised. The details of the EPR spectrum at 10 K are also consistent, in the frame of dipolar approximation, with the model of four interacting spins at the nodes of the supramolecular assembling., 2007年02月, INORGANIC CHEMISTRY, 46 (3), 660 - 669, doi;web_of_science

    研究論文(学術雑誌)

  • The magnetic anisotropy and assembling of the lanthanide coordination units in [Fe(bpca)(2)][Er(NO3)(3)(H2O)(4)]NO3

    Marilena Ferbinteanu; Takashi Kajiwara; Fanica Cimpoesu; Kensuke Katagiri; Masahiro Yamashita

    The magnetic properties of the title compound are discussed in correlation with the molecular and crystal structure. The bimetallic complex [Fe(bpea)(2)][Er(NO3)(3)(H2O)(4)](NO3) (where Hbpca = bis(2-pyridilcarbonyl)amine) crystallizes in the triclinic space group P1(-) exhibiting stacks of [Fe(bpca)(2)](+) and [Er(NO3)(3)(H2O)(4)] entities connected by hydrogen bonds. The [Er(NO3)(3)(H2O)(4)] units are connected by hydrogen bonds established between coordinated aqua and nitrate ligands. Static and dynamic magnetic properties are reported. The complex exhibits the magnetization lag in ac magnetic field of 10-1400 Hz, above 1.8 K, under a static magnetic field. The ab initio calculations, including ligand field and spin orbit effects illuminated the anisotropy properties of the lanthanide ions in the complex, revealing the orientation and extension of the lobes corresponding to the easy magnetization axes. (c) 2006 Elsevier Ltd. All rights reserved., 2007年06月, POLYHEDRON, 26 (9-11), 2069 - 2073, doi;web_of_science

    研究論文(学術雑誌)

  • Versatile vapochromic behavior accompanied by a phase change between charge-polarization state and charge-density-wave state in a quasi-one-dimensional iodo-bridged dinuclear platinum mixed-valence compound, [{NH3(CH2)(5)NH3}(2)]-[Pt-2(pop)4I]center dot 4H(2)O

    Masahiro Yamashita; Kouichi Takizawa; Satoshi Matsunaga; Daisuke Kawakami; Hiroaki Iguchi; Shinya Takaishi; Takashi Kajiwara; Fumiyasu Iwahori; Tomohiko Ishii; Hitoshi Miyasaka; Ken-ichi Sugiura; Hiroyuki Matsuzaki; Hideo Kishida; Hiroshi Okamoto

    This communication describes versatile vapochromic behavior that is accompanied by a phase change between charge-polarization (CP) and charge-density-wave (CDW) states with increasing and decreasing temperature in [{NH3(CH2)(5)NH3}(2)][Pt-2(pop)(4)I](.)4H(2)O (pop = P2H2O52-) (1)., 2006年09月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 79 (9), 1404 - 1406, doi;web_of_science

    研究論文(学術雑誌)

  • Ferromagnetic coupling promoted by k(3)N : k(2)N bridging system

    Asako Igashira-Kamiyama; Takashi Kajiwara; Takumi Konno; Tasuku Ito

    Syntheses, structures, and magnetic properties of novel trinuclear complexes of the same motif [M{Cu(pz(2)bg)(2)}M](4+) (M) Cu-II, Ni-II, Co-II, Mn-II), catena-[Cu-2{Cu(pz(2)bg)(2)}(Hpz)(2)(PhSO3)(2)](PhSO3)(2), 4H(2)O(2, 4H(2)O), [Ni-2{Cu(pz(2)bg)(2)}(MeOH)(2)(H2O)(4)](NO3)(4)(3), [Co-2{Cu(pz(2)bg)(2)}(NO3)(2)(EtOH)(2)](NO3)(2) (4), and [Mn-2{Cu(pz(2)bg)(2)}(NO3)(4)(MeCN)(2)] (5), which include the complex ligand [Cu(pz(2)bg)(2)] (1), are reported (Hpz) pyrazole, pz(2)bg(-) = di(pyrazolecarbimido)aminate; bispyrazolyl derivative of biguanidate). The reaction of Cu(ClO4)(2), 6H(2)O, sodium dicyanamide, Hpz, and PhSO3H center dot H2O (1:2:4:4) in MeOH yielded blue crystals of [Cu-2(1)(Hpz)(2)(PhSO3)(2)](PhSO3)(2), 4H(2)O (2, 4H(2)O). In 2, the tricopper(II) units, which consist of two CuII ions bridged by 1, are linked by benzenesulfonate anions to form a ladder structure. Complex 1 was isolated by removing the terminal Cu-II ions from 2 with use of Na(4)edta. Complexes 3-5 were obtained by the reaction of 1 with an excess of each M-II ion. In 2-5, the adjoining metal ions are ferromagnetically coupled via the pz(2)bg(-) ligand with J values of +7.2(1), +7.5(1), +2.7(1), and +0.3(1) cm(-1), respectively, using a spin Hamiltonian H = -2J(SM1SCu + SCuSM2). The ferromagnetic interaction was attributed to the strict orthogonality of magnetic d sigma orbitals, which are controlled by the kappa N-3:kappa N-2 bridging geometry of the pz(2)bg(-) ligands., 2006年08月, INORGANIC CHEMISTRY, 45 (16), 6460 - 6466, doi;web_of_science

    研究論文(学術雑誌)

  • Highly symmetrical tetranuclear cluster complexes supported by p-tert-butylsulfonylcalix[4]arene as a cluster-forming ligand

    T Kajiwara; T Kobashi; R Shinagawa; T Ito; S Takaishi; M Yamashita; N Iki

    Square-planar tetranuclear clusters [M-4(L)(AcO)(4)(mu(4)-OH)](-) (M = Mn-II, Co-II, and Ni-II) are synthesized using tetra-anionic p-tert-butylsulfonylcalix[4]arene (L4-) as a cluster-forming ligand. Three complexes are crystallographically isostructural, being crystallized in the triclinic crystal system with space group Pi. The calix[4]arene acts as a tetrakis fac-tridentate ligand through four phenoxo and four sulfonyl oxygen atoms to form square arrangement of four metal ions, which are further bridged by four chelating acetate ions and one hydroxo ion in a mu(4) manner to complete the hexacoordination of each metal center. Although the whole molecule of each complex is crystallographically independent, the molecule is highly symmetrical with a pseudo-four-fold axis lying on the mu(4)-OH- group. The tetranuclear clusters are stable enough to maintain the core structures even in highly dilute solution (approximate to 10 mu m), which was confirmed by mass spectroscopic study, however, bridging acetates were easily exchanged by other carboxylate chelates to form derivatives such as [M-4(L)(BzO)(4)(OH)](-). Metal-metal interactions were investigated by means of magnetic susceptibility, and it was revealed that both ferro- and antiferromagnetic interactions occur in the Ni-II complex depending on the bridging angles of Ni-O-Ni. (c) Wiley-VCH Verlag GmbH & Co., 2006年05月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (9), 1765 - 1770, doi;web_of_science

    研究論文(学術雑誌)

  • Conformation-controlled luminescent properties of lanthanide clusters containing p-tert-butylsulfonylcalix[4]arene

    T Kajiwara; K Katagiri; M Hasegawa; A Ishii; M Ferbinteanu; S Takaishi; T Ito; M Yamashita; N Iki

    Dinuclear and cubane-shaped lanthanide cluster complexes containing Eu-III and Tb-III were synthesized by step-by-step construction using p-tert-butylsulfonylcalix[4]arene as a cluster-forming ligand. The sulfonylcalixarene adopts a pinched-cone conformation in the dinuclear complexes and a cone conformation in the cubane complexes. Because the calixarene has a large pi-conjugate system expanding over the entire molecule, it behaves as a good antenna chromophore for UV and near-UV light, and a slight conformational change of the calixarene ( from cone to pinched-cone and vice versa) has an effect on the energy levels of excited S-1 and T-1 states. As a result, selectivity is observed in the luminescent properties of dinuclear and cubane-shaped systems of Eu-III and Tb-III., 2006年06月, INORGANIC CHEMISTRY, 45 (13), 4880 - 4882, doi;web_of_science

    研究論文(学術雑誌)

  • A dodecalanthanide wheel supported by p-tert-butylsulfonylcalix[4]aren

    Takashi Kajiwara; Kensuke Katagiri; Shinya Takaishi; Masahiro Yamashita; Nobuhiko Iki

    A dodecaholmium wheel of [Ho-12(L)(6)(mal)(4)(AcO)(4)(H2O)(14)] (1; mal=malonate) was synthesized by using p-tert-butylsulfonylcalix[4]arene (H4L) as a cluster-forming ligand. The wheel consists of three fragments of mononuclear A(3-) ([Ho(L)(mal)(H2O)](3-)), trinuclear B3- ([Ho(H2O)(2) (mal)(Ho(L)(AcO))(2)](3-)), and C3+ ([Ho(H2O)(2)](3+)), and an alternate arrangement of these fragments (A(3-)-C3+-B3--C3+-A(3-)-C3+-B3--C3+-) results in a wheel structure. The longest and shortest diameters of the core were estimated to be 17.7562(16) and 13.6810(13) angstrom, respectively, and the saddle-shaped molecule possesses a pocketlike cavity inside., 2006年09月, CHEMISTRY-AN ASIAN JOURNAL, 1 (3), 349 - 351, doi;web_of_science

    研究論文(学術雑誌)

  • Dynamical valence fluctuation at the charge-density-wave phase boundary in iodide-bridged Pt compound [Pt(chxn)(2)I]I-2

    Shinya Takaishi; Daisuke Kawakami; Masahiro Yamashita; Mari Sasaki; Takashi Kajiwara; Hitoshi Miyasaka; Ken-ichi Sugiura; Yusuke Wakabayashi; Hiroshi Sawa; Hiroyuki Matsuzaki; Hideo Kishida; Hiroshi Okamoto; Harutaka Watanabe; Hisaaki Tanaka; Kazuhiro Marumoto; Hiroshi Ito; Shin-ichi Kuroda

    We synthesized a novel iodo-bridged linear chain platinum compound, having the quasi-two-dimensional charge-density-wave (CDW) ground state and the smallest band gap. In this compound, we discovered an anomalous valence state in the boundary region at which the CDW phase alternates in the crystal by means of ESR, X-ray diffuse scattering, STM, and electrical resistivity. This anomalous state can be explained by the fast fluctuation between Pt-IV-(IPtII)-Pt-... and (PtI)-I-II...-Pt-IV in the double well potential. This is the first observation of the dynamical fluctuation of the CDW phase among the quasi one-dimensional halogen-bridged complexes., 2006年05月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 128 (19), 6420 - 6425, doi;web_of_science

    研究論文(学術雑誌)

  • Halogen-bridged Pt-II/Pt-IV mixed-valence ladder compounds

    Daisuke Kawakami; Masahiro Yamashita; Satoshi Matsunaga; Shinya Takaishi; Takashi Kajiwara; Hitoshi Miyasaka; Ken-ichi Sugiura; Hiroyuki Matsuzaki; Hiroshi Okamoto; Yusuke Wakabayashi; Hiroshi Sawa

    2006年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 45 (43), 7214 - 7217, doi;web_of_science

    研究論文(学術雑誌)

  • A binuclear Fe(III)Dy(III) single molecule magnet. Quantum effects and models

    Marilena Ferbinteanu; Takashi Kajiwara; Kwang-Yong Choi; Hiroyuki Nojiri; Akio Nakamoto; Norimichi Kojima; Fanica Cimpoesu; Yuichi Fujimura; Shinya Takaishi; Masahiro Yamashita

    2006年07月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 128 (28), 9008 - 9009, doi;web_of_science

    研究論文(学術雑誌)

  • Topological variation between hexa- and trithiacalix[6]arene-copper(II) complexes: From sphere to wheel by reducing the number of the sulfur bridges

    Noriyoshi Kon; Nobuhiko Iki; Takashi Kajiwara; Tasuku Ito; Sotaro Miyano

    Contrary to hexathiacalix [6] arene (H6L6S) forming [Cu-10(L-6S)(2)]-type spherical decacopper(II) complex, trithiacalix[6]arene (H6L3S), in which three sulfur bridges of H6L6S are replaced with methylenes in an alternate manner, affords nanosized wheel-shaped octanuclear complex [Cu-8(H2L3S)(4)] consisting of four [Cu2H2L3S] units., 2006年04月, CHEMISTRY LETTERS, 35 (4), 430 - 431, doi;web_of_science

    研究論文(学術雑誌)

  • New charge-transfer salts based on unsymmetrical donor DMET and metal complex anions: (DMET)(3)[Cr(isoq)(2)(NCS)(4)] and (DMET)(3)[Cr(phen)(NCS)(4)]center dot CH3CN

    Masamichi Umemiya; Makoto Goto; Norihito Kobayashi; Shinya Takaishi; Takashi Kajiwara; Masahiro Yamashita; Hitoshi Miyasaka; Ken-ichi Sugiura; Harutaka Watanabe; Daichi Suzuki; Hiroshi Ito; Shin-ichi Kuroda

    Two charge-transfer salts (DMET)(3)[Cr(isoq)(2)(NCS)(4)] (1) and (DMET)(3)[Cr(phen)(NCS)(4)]-CH3CN (2) have been prepared and characterized. The single-crystal X-ray crystallography revealed that the structures of both salts consist of segregated columns of DMET and metal complex anions. The magnetic and transport properties have shown that these salts are paramagnetic semiconductors., 2006年04月, CHEMISTRY LETTERS, 35 (4), 368 - 369, doi;web_of_science

    研究論文(学術雑誌)

  • A single-chain magnet formed by a twisted arrangement of ions with easy-plane magnetic anisotropy

    T Kajiwara; M Nakano; Y Kaneko; S Takaishi; T Ito; M Yamashita; A Igashira-Kamiyama; H Nojiri; Y Ono; N Kojima

    2005年07月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 127 (29), 10150 - 10151, doi;web_of_science

    研究論文(学術雑誌)

  • Novel excited quintet state in porphyrin: Bis(quinoline-TEMPO)-yttrium-tetraphenylporphine complex

    L Maretti; SSM Islam; Y Ohba; T Kajiwara; S Yamauchi

    New mono- and bis[4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxy](meso-tetraphenylporphyrinato)yttrium(III) complexes have been synthesized, and the properties of the excited states generated by photoexcitation of porphyrin were studied by time-resolved (TR) and pulsed two-dimensional electron paramagnetic resonance (EPR) spectroscopy. A TR-EPR spectrum was observed in the quartet (S = 3/2) or quintet (S = 2) states generated from interactions of one or two radicals with the photoexcited triplet state of the porphyrin. The zero-field splitting D values of these states were analyzed in terms of those of the triplet and the radical-triplet pair. The spin states of the excited states were definitely assigned by measuring the nutation frequencies with pulsed EPR., 2005年12月, INORGANIC CHEMISTRY, 44 (25), 9125 - 9127, doi;web_of_science

    研究論文(学術雑誌)

  • 1,3,5-triazapentanediene, a novel tridentate ligand that bridges two metal ions in kappa N-1 :kappa N-2 bridging mode with C-2 symmetry

    T Kajiwara; T Ito

    The new mononuclear complexes [Ni(Htap)(2)](ClO4)(2) (1) and [Ni(tap)(Htap)]ClO4 (2) were synthesized by the reaction of nickel(II) perchlorate and 1,3,5-triazine (Htap = 1,3,5-triazapentanediene). In 1 and 2, neutral Htap and a monoanionic tap- coordinate in a square-planar mode to the nickel(II) ions (low-spin state) in a bidentate, chelating fashion. Using the central N of tap- of 2 as a donor atom, multinuclear complexes [{Cu(tren)}(2){Ni(tap)(2)]}(ClO4)(4) (3) and [Ni(Htap)(2)](2)-[Ni{Ni(tap)(Htap)}(2)(NCS)(4)][Ni{Ni(tap)(Htap)}(NCS)(5)](2) (4) were synthesized. In both complexes, tap- binds two metal ions in a kappa(1)N:kappa(2)N bridging mode, with C-2 symmetry along the Ni-Cu axis for 3 and Ni-Ni axis for 4. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)., 2004年08月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (15), 3084 - 3088, doi;web_of_science

    研究論文(学術雑誌)

  • Octalanthanide wheels supported by p-tert-butylsulfonylcalix[4]arene

    T Kajiwara; HS Wu; T Ito; N Iki; S Miyano

    2004年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 43 (14), 1832 - 1835, doi;web_of_science

    研究論文(学術雑誌)

  • Ba19In9, a subnitride containing isolated [In-5](5-) and [In-8](12-) Zintl anions

    H Yamane; S Sasaki; T Kajiwara; T Yamada; M Shimada

    Single crystals of nonadecabarium nonaindium nonanitride, Ba19In9N9, were synthesized by the Na flux method under N-2 pressure. The compound crystallizes in the monoclinic space group C2/m, with Z = 2. Polyanionic indium clusters [In-5](5-) and [In-8](12-) are surrounded by Ba2+ cations and are located in a at cage built of linked nitrogen-centred NBa6 octahedra. The structural formula is expressed as (Ba38N18)[In-5](2)[In-8]., 2004年10月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 60, I120 - I123, doi;web_of_science

    研究論文(学術雑誌)

  • A p-tert-butyldithiacalix[4]arene-copper(II) complex having double-cone shape of unique heteroditopic inclusion behavior

    N Kon; N Iki; T Kajiwara; T Ito; S Miyano

    X-ray diffraction revealed a single crystal of a Cu(II) complex of p-tert-butyldithiacalix[4]arene 5 (H4L) to be [CU3(HL)(H2L)(AcO)], in which three Cu(II) ions are sandwiched by two calixarene ligands including different guest molecules, CHCl3 and hexane, in each cone-shaped cavity., 2004年08月, CHEMISTRY LETTERS, 33 (8), 1046 - 1047, web_of_science

    研究論文(学術雑誌)

  • Single crystal growth of manganese gallium nitride using Mn-Ga-Na melt

    M Aoki; H Yamane; M Shimada; T Kajiwara

    Manganese gallium nitride (Mn4-xGaxN) single crystals as well as Mn-doped GaN single crystals were prepared by heating a Mn-Ga-Na melt at 750degreesC and 5 MPa of N-2 pressure. The Mn4-xGaxN crystals had the cubic anti-perovskite-type structure (space group: Pm (3) over barm) with a lattice parameter a = 3.8886(9) Angstrom. The single crystals exhibited magnetic transitions from a ferrimagnetic phase with a spin-glass-like disorder to an antiferromagnetic phase at 107 K, and then to a paramagnetic phase at 270 K. From these magnetic transition temperatures, the composition of the Mn4-xGaxN single crystals was estimated to be Mn3.07Ga0.93N. (C) 2003 Elsevier B.V. All rights reserved., 2004年02月, JOURNAL OF ALLOYS AND COMPOUNDS, 364 (1-2), 280 - 282, doi;web_of_science

    研究論文(学術雑誌)

  • Bis[tris(2,2 '-bipyridine-kappa N-2,N ')ruthenium(II)] hexacyanoferrate(III) chloride octahydrate

    K Sakai; Y Uchida; T Kajiwara; T Ito

    In the title compound, [Ru-II(C10H8N2)(3)](2)[Fe-III(CN)(6)]Cl.8H(2)O, the [Ru(bpy)(3)](2+) (bpy is 2,2'-bipyridine) cations and water molecules afford intriguing microporous honeycomb layers, while the [Fe(CN)(6)](3-) anions and the remainder of the water molecules form anionic sheets based on extensive hydrogen-bonding networks. The cationic and anionic layers alternate along the c axis. The Fe atom in [Fe(CN)(6)](3-) lies on an inversion centre and the axial cyano ligands are hydrogen bonded to the water molecules encapsulated within the micropores [N...O = 2.788 (5) Angstrom], giving an unusual interpenetration between the cationic and anionic layers. On the other hand, the in-plane cyano ligands are relatively weakly hydrogen bonded to the water molecules [N...O = 2.855 (7) and 2.881 (8) Angstrom] within the anionic sheets., 2004年02月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 60, M65 - M68, doi;web_of_science

    研究論文(学術雑誌)

  • p-tert-Butylthiacalix[6]arene as a clustering ligand. Syntheses and structures of Co-5(II), Ni-4(II), and mixed-metal (MNi4II)-Ni-II (M = Mn, Co, and Cu) cluster complexes, and a novel metal-induced cluster core rearrangement

    T Kajiwara; R Shinagawa; T Ito; N Kon; N Iki; S Miyano

    Using p-tert-butylthiacalix[6]arene (H6L) as a clustering ligand, five cluster complexes having Co-5(II) (2), Ni-4(II) (3) and (MNi4II)-Ni-II (M = COII (4), Mn-II (5), and Cu-II (6) cores were synthesized. In all the complexes except for 3, a pinched conic L6- acts as a pentanucleating ligand that involves a similar pyramidally arranged cluster core. Each mixed metal complex 4-6 involves four tetragonally arranged Ni-II ions occupying the basal plane of the pyramid and a M-II ion placed at the apex position. In 3, H2L4- is in a cone conformation and the four Ni-II ions are arranged on the donor surface of H2L4- in a zigzag manner. The mixed metal complexes 4-6 are synthesized by reacting 3 and the appropriate M(AcO)(2) in a 1: 1 ratio with a novel metal-induced core rearrangement occurring. In this reaction, the insertion of a M-II ion at the apex position forces the calixarene to take a cone conformation and the Ni-4(II) array rearranges to form a tetragonal cluster., 2003年12月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 76 (12), 2267 - 2275, doi;web_of_science

    研究論文(学術雑誌)

  • A ferroelectric barium titanate, BaTi2O5

    T Kimura; T Goto; H Yamane; H Iwata; T Kajiwara; T Akashi

    The crystal structure of monobarium dititanium pentaoxide, BaTi2O5, synthesized by a floating-zone method, was studied by X-ray diffraction. Previous reports describe the structure as being in the monoclinic centrosymmetric space group C2/m. We have recently found that this material exhibits ferroelectricity, and therefore BaTi2O5 should have lower symmetry. The crystal structure of BaTi2O5 was refined in space group C2, revealing a displacement of the Ti atoms along the b axis. This result is consistent with the fact that the ferroelectricity of BaTi2O5 was only observed along the b axis., 2003年12月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 59, I128 - I130, doi;web_of_science

    研究論文(学術雑誌)

  • Controlling the construction of trinuclear, 1-D, and 2-D Ni(II)Fe(II)/Fe(II)Fe(II) complexes: selective syntheses, structures, and magnetic properties

    A Kamiyama; T Noguchi; T Kajiwara; T Ito

    The reaction of [Ni(bpca)(2)] (1) and [Fe(H2O)(6)](ClO4)(2) gave a trinuclear complex 3, five 1-D chain complexes 4a - e, and a 2-D honeycomb complex 5. The selective syntheses of these complexes were achieved by controlling the reaction conditions such as reaction stoichiometry, solvents, and the presence/absence of supporting ligands. 3 consists of a central {Fe(trans-H2O)(2)}(2+) moiety and two units of 1 acting as terminal bidentate ligands. 4a - e consist of an alternating arrangement of Fe(II) ions and 1 which acts as a bis-bidentate bridging ligand. 5 has a honeycomb structure with hexagons involving twelve metal ions, six Ni( II) ions in 1 and six Fe( II) ions, and holds the large cavity which includes counter ions, chloroform, and water molecules. The reaction of [Fe(bpca)(2)] (2) and [Fe(H2O)(6)](ClO4)(2) also gave a 2-D honeycomb complex 6 which is isostructural to 5. Magnetic data for 3 and 4a indicate a ferromagnetic interaction between adjoining Ni(II) ions and the Fe(II) ions, due to the strict orthogonality of the magnetic orbitals., 2003年06月, CRYSTENGCOMM, 5, 231 - 237, doi;web_of_science

    研究論文(学術雑誌)

  • Ferromagnetic interactions through control of the bridging geometry

    T Kajiwara; A Kamiyama; T Ito

    A novel trinuclear Ni(II)-Cu(II)-Ni(II) complex (3) and three Cu(II)-Cu(II) (4), Ni(II)-Cu(II) (5), and Mn(II)-Cu(II) (6) alternating chain complexes were synthesized using the complexed ligand [Cu(bptap)(2)] (1) which acts as a bis-mer- tridentate ligand (bptap(-) = 2,4-bis(2-pyridyl)-1,3,5-triazapentanedienate). In all complexes, two adjoining metal ions are connected by bptap- in a kappa(2)N:kappa(3)N bridging fashion with local C-2 symmetry. The bridging geometry forces the two dsigma orbitals directed towards the ligating atoms to orthogonal to each other. Ferromagnetic interaction occurs between Cu(II)-Cu(II), Cu(II)-Ni(II), and Cu(II)-Mn(II) due to the orthogonality of the magnetic orbitals with the magnitudes of J = 1.1 cm(-1) for 3 (H = -2J(S-Nil.S-Cu +S-Cu.S-Ni2)), J = 1.4 cm(-1) for 4 (H = -2JSigma(i) S-Cui SCul + 1), and theta = 7.5 K for 5 and 1.1 K for 6 (Curie-Weiss model), respectively. (C) 2003 Elsevier Science Ltd. All rights reserved., 2003年07月, POLYHEDRON, 22 (14-17), 1789 - 1793, doi;web_of_science

    研究論文(学術雑誌)

  • Synthesis and crystal structure analysis of Sr8Cu3In4N5 and Sr0.53Ba0.47CuN

    H Yamane; S Sasaki; S Kubota; M Shimada; T Kajiwara

    Single crystals of new quaternary compounds Sr8Cu3In4N5 and Sr0.53Ba0.47CuN were prepared, respectively, from a Sr-Cu-In-Na melt under 7 MPa of N-2 and from a Sr-Ba-Cu-In-Na melt under 0.5 MPa of N-2 by slow cooling from 1023 to 823 K. The crystal structures were determined by single-crystal X-ray diffraction. Sr8Cu3In4N5 has an orthorhombic structure (space group, Immm, Z=2, a=3.8161(5)Angstrom, b=12.437(2),Angstrom, c=18.902(2)Angstrom), and is isostructural with Ba8Cu3In4N5. It contains nitridocuprates of isolated units (0)[CuN2] and one-dimensional linear chains [CuN2/2] and one-dimensional indium. clusters I [In2In2/2. 0C Sr0.53Ba0.47CuN crystallizes in an orthorhombic cell, space group Pbcm, Z = 4, a = 5.4763(7) Angstrom, b = 9.2274(12) Angstrom, c = 9. 0772(12) Angstrom. The structure contains infinite zig-zag chains (1)(proportional to) [CuN2/2] which kink at every second nitrogen atom. (C) 2002 Elsevier Science (USA). All rights reserved., 2003年02月, JOURNAL OF SOLID STATE CHEMISTRY, 170 (2), 265 - 272, doi;web_of_science

    研究論文(学術雑誌)

  • Di-mu-pivalato-bis[cis-diammineplatinum(II)] bis(perchlorate) pivalic acid solvate

    K Sakai; E Ishigami; K Yokokawa; T Kajiwara; T Ito

    The intradimer Pt-Pt distance [3.0928 (9) Angstrom] in the title compound, [Pt-2(mu-C5H9O2)(2)(NH3)(4)](ClO4)2.C5H10O2, is much longer than that reported for [Pt-2(mu-C5H9O2)(2)(NH3)(4)](SO4).H2O [2.9011 (9) Angstrom; Sakai, Ishigami, Yokokawa, Kajiwara & Ito (2003). Acta Cryst. E59, m443-m445]. The complex cation has a crystallographic mirror plane perpendicular to the Pt - Pt bond. The crystal packing is stabilized by both the hydrophilic and hydrophobic layers, which stack alternately along the c axis., 2003年12月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 59, M1178 - M1180, doi;web_of_science

    研究論文(学術雑誌)

  • A head-to-tail isomer of bis[mu-2-(N '-methyl-4,4 '-bipyridinium-1-yl)acetamidato]bis[cis-diammineplatinum(II)] hexaperchlorate dihydrate

    K Sakai; Y Ikuta; T Tsubomura; K Kato; Y Yokoyama; T Kajiwara; T Ito

    In the title compound, [Pt-2(mu-C13H14N3O)(2)(NH3)(4)](ClO4)(6).2H(2)O, the dinuclear Pt-II cation is found to be a head-to-tail isomer having pseudo-C-2 symmetry. Two positively charged viologen moieties tethered to the diplatinum unit are located at the farthest position to minimize the electrostatic repulsion between the moieties, and also serve as relatively strong electron-withdrawing groups, giving rise to a very long intradimer Pt...Pt distance [3.0852 (13) Angstrom] which is the longest distance among those reported for amidate-bridged cis-diammineplatinum(II) dimers to date., 2003年09月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 59, M780 - M783, doi;web_of_science

    研究論文(学術雑誌)

  • A head-to-head isomer of bis(mu-N-methylisonicotinamidato)bis[cis-diammineplatinum(II)] tetraperchlorate

    K Sakai; M Shiomi; T Tsubomura; K Kato; Y Yokoyama; T Kajiwara; T Ito

    In the title compound, [Pt-2(C7H8N2O)(2)(NH3)(4)](ClO4)(4), the head-to-head isomer of the PtII dimer has a mirror plane through the Pt-Pt bond axis. The intradimer Pt-Pt distance is 3.0569 (8) Angstrom, while the shortest interdimer Pt...Pt distance is 7.2325 (9) Angstrom. Two adjacent dimers are associated with one another, with a pi-stacking interaction between the N-methyl-pyridinium moieties, where the plane-to-plane separation is 3.27 (1) Angstrom., 2003年08月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 59, M559 - M561, doi;web_of_science

    研究論文(学術雑誌)

  • A head-to-head isomer of di-mu-alpha-pyrrolidinonato-bis[cis-diammine-bromoplatinum(III)] dinitrate

    K Sakai; T Sakamoto; T Kajiwara; T Ito

    In the title compound, [Pt2Br2(C4H6NO)(2)(NH3)(4)](NO3)(2), the intradimer Pt-Pt distance is 2.6476 (4) Angstrom. The axial Pt-III-Br bond distances at the N-4- and N2O2-coordinated sites are 2.5647 (9) and 2.5889 (8) Angstrom, respectively. The two Pt coordination planes are tilted by 18.1 (3)degrees, and the average torsional twist of the ligands about the Pt-Pt axis is estimated as 1.0degrees., 2003年07月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 59, M553 - M555, doi;web_of_science

    研究論文(学術雑誌)

  • Di-mu-pivalato-bis[cis-diammineplatinum(II)] sulfate monohydrate

    K Sakai; E Ishigami; K Yokokawa; T Kajiwara; T Ito

    The title compound, [Pt-2(NH3)(4)(C5H9O2)(2)](SO4) . H2O, does not form an infinite chain, but has discrete dimeric cations in the crystal structure. The intradimer Pt - Pt distance in the pivalate dimer [2.9011 (9) Angstrom] is effectively shorter than that reported for the acetate analog [2.9713 (8) Angstrom], demonstrating the strong electron-donating property of the bridging pivalate ligand., 2003年07月, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 59, M443 - M445, doi;web_of_science

    研究論文(学術雑誌)

  • A head-to-head isomer of di-mu-pivalamidato-kappa N-4,O-bis[(1,10-phenanthroline-kappa N-2,N ')platinum(II)] dinitrate dihydrate

    K Sakai; M Kurashima; N Akiyama; N Satoh; T Kajiwara; T Ito

    In the title compound, [Pt-2(C5H10NO)(2)(C12H8N2)(2)](NO3)(2).2H(2)O, the intradimer Pt - Pt distance is relatively short [2.8489 (17) Angstrom], which must be due to the strong intramolecular pi-pi-stacking interactions between the phenanthroline moieties. The dimers stack along the c axis, forming one-dimensional columns in which very intriguing d - d, pi-pi and d-pi interactions exist. Although the dimer - dimer Pt...Pt distances are very long [4.340 (2) and 4.231 (2) Angstrom], some short interdimer Pt...C contacts leading to strong interdimer associations are found [3.325 (19) and 3.402 (19) Angstrom]., 2003年09月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 59, M345 - M349, doi;web_of_science

    研究論文(学術雑誌)

  • Zinc(III) slides on a ligand surface: The X-ray crystal structure and dynamic behavior in solution of [Zn(H2L)(tacn)]

    T Kajiwara; S Yokozawa; T Ito; N Iki; N Morohashi; S Miyano

    2002年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 41 (12), 2076 - 2078, web_of_science

    研究論文(学術雑誌)

  • Synthesis, structure, and ferromagnetic behavior of decacopper(II) cluster complex supported by hexaanionic p-tert-butylthiacalix[6]arene

    T Kajiwara; N Kon; S Yokozawa; T Ito; N Iki; S Miyano

    2002年09月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 124 (38), 11274 - 11275, doi;web_of_science

    研究論文(学術雑誌)

  • New partially oxidized 1-D platinum chain complexes consisting of carboxylate-bridged cis-diammineplatinum dimer cations

    K Sakai; E Ishigami; Y Konno; T Kajiwara; T Ito

    2002年10月, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 124 (41), 12088 - 12089, doi;web_of_science

    研究論文(学術雑誌)

  • Syntheses, Structures, and Properties of Trinuclear Complexes [M(bpca)2{M'(hfac)2}2], Constructed with the Complexes Bridging Ligand [M(bpca)2] [M, M’ = Ni(II), Mn(II);Cu(II), Mn(II); Fe(II), Mn(II); Ni(II), Fe(II); and Fe(II), Fe(II); Hbpca = bis(2-pyrid

    梶原孝志

    Five trinuclear complexes [M(bpca)(2){M'(hfac)(2)}(2)] (where MM'(2) = NiMn2, CuMn2, FeMn2, NiFe2, and FeFe2; Hbpca = bis(2-pyridyloarbonyl)amine; and Hhfac = hexafluoroacetylacetone) were synthesized almost quantitatively by the reaction of [M(bpca)(2)] and [M'(hfaC)(2)] in 1:2 molar ratio, and their structures and magnetic properties were investigated. Three complexes, with M' = Mn, crystallize in the same space group, Pna2(1), whereas two complexes, with M' = Fe, crystallize in P4(1), and complexes within each set are isostructural to one another, In all complexes, [M(bpca)(2)] acts as a bis-bidentate bridging ligand to form a linear trinuclear complex in which three metal ions are arranged in the manner W-M-W. The central metal ion is in a strong ligand field created by the N-6 donor set, and hence the Fe(II) in the {Fe(bpca)(2)} moiety is in a low-spin state. The terminal metal ions (M') are surrounded by O-6 donor sets with a moderate ligand field, which leads to the high-spin configuration of Fe(II). Three metal ions in all complexes are almost collinear, and metal-metal distances are ca. 5,5 Angstrom. The, magnetic behavior of NiMn2 and NiFe2 shows a weak ferromagnetic interaction between the central Ni(II) ion and the terminal Mn(II) or Fe(II) ions. In these complexes, sigma-spin orbitals of the central Ni(II) ion and those of terminal metal ions have different symmetry about a 2-fold rotation axis through the Ni-N-amide-M'(terminal) atoms, and this results in orthogonality between the neighboring sigma-spin orbitals and thus ferromagnetic interactions., 2002年02月, INORGANIC CHEMISTRY, 41 (3), 507 - 512, doi;web_of_science

    研究論文(学術雑誌)

  • Morphology and polarity of GaN single crystals synthesized by the Na flux method

    M Aoki; H Yamane; M Shimada; T Kajiwara; S Sarayama; FJ DiSalvo

    The correlation between morphology and polarity was investigated for GaN single crystals synthesized by the Na flux method. The polarity was identified by using anomalous X-ray dispersion. Colorless transparent prismatic single crystals were classified into three types. The first had a smooth blasal plane face and no hexagonal pyramidal faces, the second had smooth pyramidal faces, and the third had a rough basal plane face and rough pyramidal faces. The prismatic crystals with smooth surfaces had N-polarity and grew in the -c direction, whereas the crystals having rough surfaces had Ga-polarity and grew in the +c direction. In colorless transparent platelet single crystals, one side of the basal planes had a mirror smooth surface, while the other side had many step edges and hexagonal pits. The smooth basal plane and the rough basal plane were the (0001) N-face and (0001) Ga-face, respectively. Black pyramidal crystals had a smooth (0001) basal plane face corresponding to the Ga-face., 2002年01月, CRYSTAL GROWTH & DESIGN, 2 (1), 55 - 58, doi;web_of_science

    研究論文(学術雑誌)

  • Complexed bridging ligand, {Cu(bptap)(2)}, as a ferromagnetic coupler

    T Kajiwara; A Kamiyama; T Ito

    A novel complexed bridging ligand [Cu(bptap)(2)] which acts as a ferromagnetic coupler forms one dimensional chain consisting of tri-copper(II) [Cu-2{Cu( bptap)(2)}](4+) units in which adjoining copper( II) ions are ferromagnetically coupled., 2002年, CHEMICAL COMMUNICATIONS, (12), 1256 - 1257, doi;web_of_science

    研究論文(学術雑誌)

  • Syntheses, structures, and magnetic properties of multinuclear complexes constructed with complexed ligands, [M(bpca)(2)](+) (M = Cr(III), Fe(III), Co(III); Hbpca = bis(2-pyridylcarbonyl)amine)

    T Kajiwara; R Sensui; T Noguchi; A Kamiyama; T Ito

    Two trinuclear complexes [Fe(II)(ClO4)(2) {M(III)(bpca)(2)}(2)](ClO4)(2) (M=Co for 1 and Fe for 2) and three chain complexes catena[Fe(II)(ClO4)(2) {M(III)(bpca)(2)}] ClO4 (M=Co for 3, Cr for 4, and Fe for 5) were synthesized and structures for all complexes and magnetic properties for 3-5 were investigated (Hbpca=bis(2-pyridylcarbonyl)amine). All of these complexes consist of {trans Fe(II)(ClO4)(2)} unit(s) and cationic complexed ligands, {M(III)(bpca)(2)}(+), in an alternate arrangement. In 3-5, perchlorate anions in the {trans -Fe(II)(ClO4)(2)} unit are bound to a high-spin Fe(II) ion with relatively short distances in the range from 2.131(3) to 2.157(3) Angstrom. The cationic complex ligands in 1 and 2 act as a bidentate terminal ligand whereas in 3-5 they act as a bis-bidentate bridging ligand. In 3, very weak ferromagnetic interaction occurs between Fe(II) ions via the diamagnetic complexed ligand [Co(III)(bpca)(2)](+). In both 4 and 5 antiferromagnetic interactions occur between high-spin Fe(II) and Cr(III) ions in 4 and high-spin Fe(II) and low-spin Fe(III) ions in 5, respectively. Compound 5 shows ferrimagnetic behavior at low temperature. A plot of 1/chi(M) versus T above 50 K for 4 and 5 obey the Curie-Weiss law with negative Weiss constants of theta = -12.5(4) K for 4 and -15.3(6) K for 5, respectively. The temperature dependence of chi(M)T for 5 was further analyzed by the Seiden model from which the J value was estimated as -13.8(3) cm(-1) (H = -J[S-Fe(II)i + SFe(II)i+1].S-Fe(III)i). (C) 2002 Elsevier Science B.V. All rights reserved., 2002年09月, INORGANICA CHIMICA ACTA, 337, 299 - 307, web_of_science

    研究論文(学術雑誌)

  • Synthesis and Structure of Ba8Cu3In4N5 with Nitridocuprate Groups and One-Dimensional Infinite Indium Clusters

    梶原孝志

    2002年, J. Solid State Chem.,, 163, 449-454

  • Cage-type hexacopper(II) complex formed by chloride template

    A Kamiyama; T Kajiwara; T Ito

    A novel cage complex [CU6C](MeO)(2)(pz)(9)] (1) was synthesized via a chloride ion template reaction and structurally characterized. In 1, two trinuclear units, {Cu-3 (MeO)(pz)(3))(2+), are linked by three pyrazolate ligands, six copper(II) ions form a trigonal prism, and a chloride ion is located at the center of the cage. 1 shows rather strong anti ferromagnetic coupling between the copper(II) ions through the MeO- and pyrazolate ligands., 2002年10月, CHEMISTRY LETTERS, (10), 980 - 981, web_of_science

    研究論文(学術雑誌)

  • Ba14Cu2In4N7, a new subnitride with isolated nitridocuprate groups and indium clusters

    H Yamane; S Sasaki; S Kubota; T Kajiwara; M Shimada

    Single crystals of Ba14Cu2In4N7, tetradecabarium dicopper tetraindium heptanitride, were synthesized by slow cooling from 1023 K at 7 MPa of N-2 using an Na flux. The compound crystallizes in the monoclinic space group P2/m with Z = 2, and contains (0)[CuN2] nitridocuprate units and distorted (0)[In-4] clusters. One Ba atom, not connected to any N atoms, is surrounded by 12 other Ba atoms in a barium cuboctahedron. The structural formula is expressed as (Ba)Ba27N6[CuN2](4)-[In-4](2)., 2002年04月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 58, I50 - I52, doi;web_of_science

    研究論文(学術雑誌)

  • CrN single-crystal growth using Cr-Ga-Na ternary melt

    M Aoki; H Yamane; M Shimada; T Kajiwara

    Regular octahedral CrN single crystals with a maximum size of 75 mum were obtained by heating Cr-Ga-Na ternary melt at 850degreesC and 3 MPa of N-2 for 200 It. X-ray powder and single-crystal diffractometry revealed that the CrN single crystals had the cubic rock-salt structure with the lattice parameter a = 4.1467(8) Angstrom. The CrN single crystals exhibited antiferromagnetism below the Neel temperature of 290 K. (C) 2002 Elsevier Science B.V. All rights reserved., 2002年12月, JOURNAL OF CRYSTAL GROWTH, 246 (1-2), 133 - 138, web_of_science

    研究論文(学術雑誌)

  • Synthesis and structural characterization of a Pd2+ complex with p-tert-butylsulfinylcalix[4]arene

    N Morohashi; N Iki; S Miyano; T Kajiwara; T Ito

    Single-crystal X-ray analysis has shown that p-tert-butyl-sulfinylcalix[4]arene (H4L) can bind Pd2+ ion by using either S or O atoms of bridging S=O groups in addition to phenolic oxy gen atoms to form in [Pd-2(H2L)(H3L)(2)] complex., 2001年01月, CHEMISTRY LETTERS, (1), 66 - 67, web_of_science

    研究論文(学術雑誌)

  • Sulfonylcalix[4]arene as a bis-tridentate facial ligand: Syntheses and structures of dinuclear complexes, [M-2(L)(H2O)(2)(dmf)(4)] (M = Co(II), Ni(II); H4L = p-tert-butylsulfonylcalix[4]arene)

    T Kajiwara; S Yokozawa; T Ito; N Iki; N Morohashi; S Miyano

    Cobalt(II) and nickel(II) complexes with a tetraanionic ligand of p-tert-butylsulfonylcalix[4]arene were synthesized and their X-ray structures show that the calixarene acts as a bis-tridentate dinucleating ligand with the 1.2-alternate conformation., 2001年01月, CHEMISTRY LETTERS, (1), 6 - 7, web_of_science

    研究論文(学術雑誌)

  • A graphite-like complex with large cavities constructed with the complex ligand [Ni-II(bpca)(2)]

    A Kamiyama; T Noguchi; T Kajiwara; T Ito

    2000年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 39 (17), 3130 - 3132, web_of_science

    研究論文(学術雑誌)

  • Mixed-valent heptairon complex with a ground-state spin value of S=12/2 constructed from a triiron cluster ligand

    T Kajiwara; T Ito

    2000年, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 39 (1), 230 - +, web_of_science

    研究論文(学術雑誌)

  • Zinc-blende-type cubic GaN single crystals prepared in a potassium flux

    H Yamane; T Kajiwara; T Sekiguchi; M Shimada

    Single crystals of zinc-blende-type cubic GaN (c-GaN, space group F (4) over bar 3m, lattice parameter a = 4.5062(9) Angstrom) were synthesized at 750 degrees C by the reaction of Ga and N-2 in a potassium flux. The crystal structure was analyzed by single-crystal X-ray diffraction with an R1-factor of 2.1% (R1 = Sigma parallel to F-o - F-c parallel to /Sigma\F-o\), where F-o is the observed structure factor and F-c is the calculated structure factor). A peak of near-band-edge emission was observed at 3.20 eV in the cathodoluminescence spectrum measured at 25 degrees C., 2000年02月, JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS, 39 (2B), L146 - L148, web_of_science

    研究論文(学術雑誌)

  • Na3Ca2TaO6, a rock-salt superstructure phase with a fully ordered cation arrangement

    H Yamane; H Takahashi; T Kajiwara; M Shimada

    The title quaternary oxide, trisodium dicalcium tantalum hexaoxide, is isostructural with Li3Ni2TaO6, a partially ordered rock-salt phase. The Na, Ca and Ta atoms occupy octahedral sites in an orderly manner and form a cation-ordered superstructure., 2000年10月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 56, 1177 - 1178, web_of_science

    研究論文(学術雑誌)

  • [Fe(C12H8N3O2)Cl-2(ROH)], with R = Me and Et

    T Kajiwara; T Ito

    The title octahedral complexes, [bis(pyridine-2-carbonyl)aminate]dichloro (methanol)iron(III), [Fe(C12H8N3O2)Cl-2(CH4O)], and [bis (pyridine-2-carbonyl) aminate] dichloro(ethanol)iron(III), [Fe(C12H8N3O2)Cl-2(C2H6O)], both crystallize in space group P (1) over bar and have similar structures. Monoanionic bpca(-) [bis(pyridine-2-carbonyl)aminate] acts as a planar tridentate ligand in both cases. Coordination bond distances are in the range typical of high-spin Fe-III complexes. Carbon-oxygen distances are typical of a C=O double bond suggesting the negative charge of the bpca(-) ligand is localized on the central N atom., 2000年01月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 56, 22 - 23, web_of_science

    研究論文(学術雑誌)

  • Fe(II)-Fe(III) alternate ferrimagnetic chain constructed with complexed-ligand [Fe(bpca)(2)](+) (Hbpca = bis(2-pyridylcarbonyl) amine)

    T Kajiwara; T Ito

    The reaction of [Fe(bpca)(2)]. H2O with Fe(ClO4)(3). 6H(2)O in MeNO2-CHCl3 solution and MeNO2-CH2Cl2 solution afforded black crystals of a trinuclear complex, [Fe(H2O)(2) {Fe(bpca)(2)}2](ClO4)(4) (1), and a linear chain complex, catena-[Fe(ClO4)(2) {Fe(bpca)(2)}]ClO4 (2), respectively (Hbpca = bis(2-pyridylcarbonyl)amine). In both complexes, iron atoms in {Fe(bpca)2}(+) units are in a low-spin 3(+) state, whereas irons coordinated by four carbonyl oxygen atoms and two axial oxygen atoms (from coordinated water molecules or perchlorate anions) take a high-spin 2(+) state. In both 1 and 2 antiferromagnetic interactions operated between high-spin Fe(II) and low-spin Fe(III) ions. 2 shows the ferrimagnetic ordering at 2.5 K. The plot of 1/chi(m) vs T above 50 K for 2 obeys the Curie-Weiss law with a negative Weiss constant of theta = -15.3 K., 1999年, MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 335, 785 - 792, web_of_science

    研究論文(学術雑誌)

  • A trinuclear Pd2Ni complex, [(C6H5)(4)P](2)-[(PdCl3)(2)(Ni(C12H18N2O2)}]

    A Kamiyama; T Kajiwara; T Ito

    In the title complex, bis(tetraphenylphosphonium) di-mu-chloro-1:3 kappa(2)Cl, 2:3 kappa(2)Cl-tetrachloro-1 kappa(2)Cl, 2 kappa(2)Cl-mu(3)-[4,4'-(1,2-ethanediyldinitrilo)bis(pentan-2-onato)]-1 kappa C-3:2 kappa(4)O,N,N',O':3 kappa C-3'-dipalladium(II)nickel(II), (C24H20P)(2)[Pd2NiCl6(C12H18N2O2)], the trinuclear complex anion, [(PdCl3)(2){Ni(acen)}](2-), has twofold crystallographic symmetry and consists of a central {Ni(acen)} unit and two terminal {PdCl3} moieties. These are connected through Pd-C [2.120(2) Angstrom] and Cl-Ni bends [2.4919 (5) Angstrom], giving an elongated octahedral coordination geometry around the central Ni-II ion. The {PdCl3} moiety acts as a pendant ann attached to the {Ni(acen)} unit, and the geometry around the Pd atom is of the square-planar type., 1999年08月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 55, 1282 - 1284, web_of_science

    研究論文(学術雑誌)

  • Na2Ca3Ta2O9 with a simple stacking of oxygen triangular nets

    H Yamane; H Takahashi; T Kajiwara; M Shimada

    The crystal structure of the title quaternary oxide, disodium tricalcium ditantalum nonaoxide, has a distorted simple hexagonal packing of the O atoms. The Na, Ca and Ta atoms are positioned in oxygen trigonal prisms. Two oxygen prisms containing Ta atoms constitute face-sharing prisms of [Ta2O9](8-)., 1999年12月, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 55, 1978 - 1980, web_of_science

    研究論文(学術雑誌)

  • Complexed bridging ligand, [M(bpca)(2)] (M = Mn(II) or Fe(II); Hbpca = bis(2-pyridylcarbonyl)amine), as a building block for linear trinuclear complexes

    T Kajiwara; T Ito

    The antiferromagnetically coupled trimanganese complex [Mn-II(bpca)(2){Mn-II(hfac)(2)}(2)] (Hbpca = bis(2-pyridylcarbonyl)amine; Hhfac = hexafluoroacetylacetone) and its iron-manganese mixed metal derivative, [Fe-II(bpca)(2){Mn-II(hfac)(2)}(2)], were synthesized by the reaction of two equivalents of [Mn(hfac)(2)(H2O)(2)] with one equivalent of [M(bpca)(2)], the latter acting as a bridging complexed-ligand., 1998年10月, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, (20), 3351 - 3352, web_of_science

    研究論文(学術雑誌)

  • Mercury-carbon bond formation promoted by the co-ordinated ligand reaction of a beta-diiminate chelate

    T Kajiwara; R Murao; T Ito

    Reaction between [Ni(tmtaa)] and HgBr2 in dichloroethane afforded the mercury-carbon bonded tetranuclear complex [Ni(tmtaa)HgBr](2)[Hg2Br6] (H(2)tmtaa = 5,14-dihydro-6,8,15,17-tetramethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine)., 1997年08月, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, (15), 2537 - 2538, web_of_science

    研究論文(学術雑誌)

  • Hydrogenation of a delocalized diiminate six-membered chelate ring in tetraazamacrocyclic nickel(II) complexes by sodium borohydride in water - Effect of protonation-deprotonation equilibria and stereoselective reduction

    K Mochizuki; T Kondo; S Manaka; T Kajiwara; T Ito

    Charge delocalized diiminate six-membered chelate rings in the 5,7-dimethyl-1,4,8,11-tetraazacyclotetradecane-4,6-dienatonickel(II) ion(1) and the alpha,alpha'-bis(5,7-dimethyl-1,4,8,11-tetraazacyclotetradeca-4,6-dienato-6-yl)-xylenedinicke(II) ion(2) were hydrogenated in aqueous media by sodium borohydride. In the reduction reactions, control of the pH of the reaction mixture was essential, and the pH of the solution was kept during the reaction at 3 and at 5-6 for hydrogenations of 1 and 2, respectively. The delocalized diiminate chelate ring is in protonation-deprotonation equilibrium with the beta diimine form and the pK(a) of the equilibrium for 2 was determined to be 9.0 for 2a (o-xylylene bridged complex), 9.3 for 26 (m-xylylene bridged complex), and 10.0 for 2c (p-xylylene bridged complex). The appropriate pH values in the hydrogenation reactions were based on the pK(a)'s. X-ray structure analyses on two reduction products of 1 show that the chirality of the two asymmetric carbons in the cyclam ring is of the meso-form in the major reduction product whereas that in the minor product is of the racemic form. In the major reduction product of 2, two chiral carbons in each cyclam ring take the meso-form., 1996年, JOURNAL OF COORDINATION CHEMISTRY, 37 (1-4), 205 - 216, web_of_science

    研究論文(学術雑誌)

  • SYNTHESIS, STRUCTURE, AND MAGNETIC PROPERTY OF LINEAR CHLORO-BRIDGED NICKEL(II) TETRAMER WITH DINUCLEATING BIS-DIMETHYLCYCLAM LIGAND

    T KAJIWARA; T YAMAGUCHI; H OSHIO; T ITO

    A new nickel(II) complex with the composition of Ni2Cl2(L)(ClO4)2.1.5H2O (L = alpha,alpha'-bis(5R(S), 7S(R)-5,7-dimethyl-1,4,8,11-tetraazacyclotetradecan-6-yl)-o-xylene) has been prepared via a four coordinate complex [Ni2(L)] (ClO4)4.3H2O from [Ni2(mu-Br)Br2(L)]Br.H2O. The compound crystallizes in orthorhombic space group Ccm2(1) with cell parameters at -80-degrees-C, a=21.90(1), b=20.28(1), c=19.63(1) angstrom, V =8718(1) angstrom3, Z=8. The crystal consists of the cationic dinuclear unit [Ni2(mu-Cl)Cl2(L)]+, the counter anion ClO4-, and water of crystallization. In [Ni2(mu-Cl)Cl2(L)]+, three chloride ions and two nickel ions are alternately arranged in an almost linear manner, and two cyclam rings with the most stable trans-III type conformation are arranged in a face-to-face manner. This cationic dinuclear unit is further connected to each other by sharing the terminal Cl ligand to form pseudo one-dimensional chain structure of the ...Cl-Ni-Cl-Ni-Cl... type. However, one of the Cl atoms which bridges the dinuclear units is statistically disordered at two positions along the chain and thereby the repeating unit in the chain is a chloro bridged dimer of the dinucleating ligand complex. The neighboring Ni-Cl distances range from 2.568(4) to 2.855(4) angstrom. The temperature dependent magnetic behavior in the range of 25-300 K has been interpreted by the usual Heisenberg-Dirac-Van Vleck model, assuming that only three Ni(II) ions in {Ni2Cl2(L)}2 are paramagnetic. The best fit parameters were J = -48.2(3) and J' = - 11.2(3) cm-1 for H=- 2J(S1.S1') -2J' (S1.S2)., 1994年08月, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 67 (8), 2130 - 2135, web_of_science

    研究論文(学術雑誌)

  • DESIGN OF COMPLEX-LIGAND SYSTEMS BASED ON THIOURACIL - A NOVEL CYCLIC TETRAMER OF COBALT(III) WITH 1-(2-THIOURACIL-4-METHYLENE)-3,6-DIAZAHEXANE

    T KAJIWARA; T ITO

    A Schiff base derived from 2-thiouracil-4-aldehyde and dien reacts with COII (CF3SO3)(2) to afford a novel cyclic tetramer of cobalt(III) by self-assembly; the complex has a columnar cavity at its centre with an effective diameter of ca. 1.8 Angstrom., 1994年08月, JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, (15), 1773 - 1774, web_of_science

    研究論文(学術雑誌)

  • A DINUCLEATING BIS(DIMETHYLCYCLAM) LIGAND AND ITS DINICKEL(II) AND DIZINC(II) COMPLEXES WITH THE FACE-TO-FACE RING ARRANGEMENT

    T KAJIWARA; T YAMAGUCHI; H KIDO; S KAWABATA; R KURODA; T ITO

    A new dinucleating ligand (L) with two dimethylcyclam rings was synthesized. In[Ni2(mu-Br)Br2(L)]-Br.H2O and [Zn2(mu-CO3)(L)](ClO4)2.2H2O, two cyclam rings are arranged in a face-to-face manner with Br- and CO3(2-) bridging in the former (Ni-Ni = 5.802(2) angstrom) and the latter (Zn-Zn = 5.806(2) angstrom). [Zn2(mu-CO3)(L)](ClO4)2.2H2O has been obtained via the spontaneous CO2 uptake from the air by [Zn2(L)](ClO4)4., 1993年11月, INORGANIC CHEMISTRY, 32 (23), 4990 - 4991, web_of_science

  • サイエンス・オープンラボを通した化学(化学発光、金属イオンの色)学習 −大学生による演示実験を動機付けにした高等学校授業開発研究−

    中島隆行; 三方裕司; 梶原孝志; 竹内孝江; 浦康之; 高島弘; 松浦紀之

    2020年03月, 教育システム研究

  • Tetranuclear Nickel and Cobalt Complexes with an Incomplete Double-Cubane Structure-Homo- and Heterometallic Complexes and Their 1D Coordination Polymers

    Takayuki Nakajima; Keiko Seto; Andreas Scheurer; Bunsho Kure; Takashi Kajiwara; Tomoaki Tanase; Masahiro Mikuriya; Hiroshi Sakiyama

    The reactions of M(OAc)(2 center dot)4H(2)O (M = Ni, Co) with three unsymmetrical amine-did l ligands RN(CH2CH2OH)-(CH2CH2CH2OH) (H2Ln: n =1 , R = benzyl, n = 2, R = 4-methylenzyl]; n = 3, R = 2-naphthalenylmethyl) in the presence of NEt3 or pyridine in MeOH or BnOH gave the tetranuclear complexes [M-4(HLn)(2)(OAc)(6)(MeOH)(2)] {M = Ni, n = 1 (la), 2 (lb), 3 (1c) M = Co, n = 1 (4a), 2 (4b), 3 (4c)} and [M-4(HLn)(2)-(OAc)(6)(BnOH)(2)] {M = Ni, n = 1 (2a), 2 (2b), 3 (2c); M = Co, n = 1 (5a), 2 (5b), 3 (5c)}. When p-xylene-alpha,alpha'-diol was used instead of monoalcohols, the tetranuclear (M4O6) units were linked by p-xylene-alpha,alpha'-diol to form the 1D coordination polymers [M-4(HLn)(2)(OAc)(6)(p-HOH2C6H4CH2OH)](m) {M = Ni, n = 1 (3a), 2 (3b); M = Co, n = 1 (6a), 2 (6b)). The structures of 1-6 were determined by X-ray crystallography and consist of centrosymmetrical tetranuclear (M4O6)) face-shared defective double-cubane cores supported by two monodeprotonated (HLn-) ligands. The mixed-metal letranuclear complexes [Ni2.2Co1.8(HL1)(2)(OAc)(6)(MeOH)(2)] (7) and [Mn1.7Ni2.3(HL1)(2)(OAc)(5)(OMe)(2)] (8) were also synthesized by using e.quimolar amounts of Ni2+ and M2+ (M = Co, Mn) ions. X-ray crystallographic and :fluorescent analyses.revealed that 7 is isomorphous with 1a and 4a and contains.nonstoichiometric amounts of disordered Ni2+ and Co2+ ions in an average ratio of 2.2:1.8 with different occupancies for the two crystallographically independent metal centers. In contrast, 8 consists of a C-2-symmetrical face-shared defective doublecubane ((M3MnO6)-Mn-II-O-III) core with a Ni/Mn ratio of 2.3:1.7, the amounts of Ni2+ and Mn2+ ions vary depending on the metal sites, and one of the C-2 axial positions is exclusively occupied by Nin ions. Detailed magnetostru.ctural analyses on the nickel (1a, 2a, 3a) mid cobalt (4a) complexes with appropriate spin-Hamiltoulau. models showed that both iferro- and antiferromagnetic spin exchange interactions were involved within the tetranuclear units, and their extent depends on the combination of the metal ions and -the ligand systems in a delicate fashion., 2014年10月, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (29), 5021 - 5033, doi;web_of_science

    研究論文(学術雑誌)

  • Magnetic anisotropy and molecular assembling in d complex cation-f complex anion type coordination compounds

    Marilena Ferbinteanu; Fanica Cimpoesu; Takashi Kajiwara; Masahiro Yamashita

    The system [Fe(bpca)(2)][Er(NO(3))(4)(H(2)O)(2]) (1) (Hbpca = bis(2-pyridil-carbonyl)amine) is a complex cation-complex anion type coordination compound consisting of distinct d and f units, interlinked by hydrogen bonds. Particularly, the association of f-type complex anions in dimers is remarked and discussed. The energy decomposition analyses based on DFT calculations offered supplementary insight into the coordination effects at the lanthanide ions and the hydrogen bond driven supramolecular association of the complex units. Special ab initio procedures and subsequent modeling afforded the computation of anisotropic magnetization tensors of the [Er(NO(3))(4)(H(2)O)(2)(-) f-type units. The computed results are in line with the experimental data for compound 1. (C) 2008 Elsevier Masson SAS. All rights reserved., 2009年04月, SOLID STATE SCIENCES, 11 (4), 760 - 765, doi;web_of_science

    研究論文(学術雑誌)

  • Mixed Charge-Ordering State of MMX-Type Quasi-One-Dimensionl Iodide-Bridged Platinum Complexes with Binary Countercations

    H. Iguchi; S. Takaishi; T. Kajiwara; H. Miyasaka; M. Yamashita; H. Matsuzaki; H. Okamoto

    2008年12月, Journal of the American Chemical Society, 130, 17668-17669, doi

  • Transition metal and lanthanide cluster complexes constructed with thiacalix[n]arene and its derivatives

    Takashi Kajiwara; Nobuhiko Iki; Masahiro Yamashita

    This review deals with the formations, structures, and properties of transition metal and lanthanide clusters supported by thiacalix[n]arene and its oxidized derivatives, sulfinylcalix[4]arene and sulfonylcalix[4]arene. Each thiacalix[n]arene possesses donor atoms both on the lower rim position (phenol oxygen atoms) and on the cyclic framework itself (-S-, -SO-, or -SO2-), and behaves as a multidentate multi-nucleating ligand to support the formation of a phenoxo-bridged cluster core. For first row transition metals, calix[4]arenes offer a platform for assembling the metal ions via four fac-tridentate coordination sites, and planar tri- and tetra-nuclear clusters are formed. A larger and more flexible thiacalix[6]arene could bind up to five metal ions inside the coordination cavity formed when it adopts the pinched cone conformation. Sulfonylcalix[4]arene shows a strong affinity to lanthanide ions through phenoxo and sulfonyl oxygen donors, and yields a variety of cluster compounds involving di-, tetra-, octa-, and dodeca-nuclear cores, achieved by controlled synthetic conditions. (C) 2007 Elsevier B.V. All rights reserved., 2007年07月, COORDINATION CHEMISTRY REVIEWS, 251 (13-14), 1734 - 1746, doi;web_of_science

    研究論文(学術雑誌)

  • Halogen-Bridged Two-Leg Ladder PtII-PtIV Mixed-Valence Complexes: Syntheses, Structures and Optical

    M. Yamashita; D. Kawakami; S. Matsunaga; S. Takaishi; T. Kajiwara; H. Miyasaka; K. Sugiura; H. Matsuzaki; H. Kishida; H. Okamoto; Y. Wakabayashi; H. Sawa

    2006年04月, Angew. Chem. Int. Ed.,, 45, 7214 - 7217

    研究論文(学術雑誌)

  • Synthesis and crystal structures of CaY2Ge3O10 and CaY2Ge4O12

    H Yamane; R Tanimura; T Yamada; J Takahashi; T Kajiwara; M Shimada

    New compounds Cay(2)Ge(3)O(10) and CaY2Ge4O12 were prepared by heating mixtures of CaCO3, Y2O3 and GeO2 at 1200 degrees C. CaY2Ge3O10 is stable at 1300 degrees C, while CaY2Ge4O12 decomposes into a melt and CaY2Ge3O10 at approximately 1250 degrees C. We obtained single crystals of CaY2Ge3O10 by cooling a sample with an initial composition of Ca:Y:Ge = 1:2:8 from 1300 degrees C with a rate of -6 degrees C/h. The crystal structure of CaY2Ge3O10 was determined by single crystal X-ray diffraction. CaY2Ge3O10 crystallizes in the monoclinic space group P2(1/)c with a = 6.0906(8), b = 6.8329(8), c = 18.752(2) angstrom and beta = 109.140(3)degrees, Z = 4. and R, = 0.029 for I > 2 sigma(I). In the structure of CaY2Ge3O10, Ca and Y atoms are situated disorderly in three 7-fold coordination sites between isolated Germanate groups of triple GeO4 tetrahedra, Ge3O10. The structural formula of CaY2Ge3O10 is expressed as (Ca0.45Y0.55)(Ca0.46Y0.54)(Ca0.09Y0.91)Ge3O10. The crystal structure of CaY2Ge4O12 was analyzed by the Rietveld method for the X-ray powder diffraction pattern. CaY2Ge4O12 is isotypic with SrNa2P4O12, crystallizing in the orthorhonibic space group P4/nbm, a = 9.99282(6), c = 5.06701(4) angstrom, Z = 2, R-wp = 0.092, R-p = 0.067. CaY2Ge4O12 contains four-membered GeO4-tetrahedra rings, Ge4O12. Eight-fold coordinated square-anitiprism sites and 6-fold octahedral sites between the layers of the Ge4O12 rings are occupied by Y atom and Ca/Y atoms, respectively The structural formula is Y(Ca0.5Y0.5)(2)Ge4O12. (c) 2005 Elsevier Inc. All rights reserved., 2006年01月, JOURNAL OF SOLID STATE CHEMISTRY, 179 (1), 289 - 295, doi;web_of_science

    研究論文(学術雑誌)

  • Versatile Vapochromic Behavior Accompanied by Phase Change between Charge-Polarization State and

    M. Yamashita; K. Takizawa; S. Matsunaga; D. Kawakami; H. Iguchi; S. Takaishi; T.,Kajiwara; F. Iwahori; T. Ishii; H. Miyasaka; K. Sugiura; H. Matsuzaki; H. Kishida; H. Okamoto

    2006年, Bull. Chem. Soc. Jpn.,, 79, 1404 - 1406, doi

    研究論文(学術雑誌)

  • Single crystal growth of Mn2N using an In-Na flux

    M. Aoki; H. Yamane; M. Shimada; T. Kajiwara

    2004年05月05日, Mater. Res. Bull., 39 (6), 827 - 832, doi

    研究論文(学術雑誌)

  • Anisotropy of Spin–Lattice Relaxations in Mononuclear Tb3+ Single-Molecule Magnets

    Piotr Konieczny; Robert Pel̷ka; Yuka Masuda; Shiomi Sakata; Saori Kayahara; Natsumi Irie; Takashi Kajiwara; Stanisl̷aw Baran

    2020年04月09日, The Journal of Physical Chemistry C, 124 (14), 7930 - 7937, doi;url

    研究論文(学術雑誌)

MISC

  • Solvent induced reversible change of magnetic properties in a Fe(II)-Fe(III) single chain magnet

    Yukihiro Kaneko; Takashi Kajiwara; Hisanori Yamane; Masahiro Yamashita

    A single chain magnet (SCM), catena-[Fe-II(ClO4)(2)(Fe-III(bpca)(2)})ClO4 (1) includes three nitromethane molecules per a Fe(II)-Fe(III) unit as crystallized solvent which occupy the pores surrounded by four chains. Compound I can release or reabsorb these MeNO2 molecules like "sponges" possessing the chain structure of 1, accompanied by a reversible changing of SCM behavior during this process. Compound I is the first nano-magnet which shows the solvent induced reversible change of magnetic properties. (c) 2006 Elsevier Ltd. All rights reserved., PERGAMON-ELSEVIER SCIENCE LTD, 2007年06月, POLYHEDRON, 26 (9-11), 2074 - 2078, doi;web_of_science

  • A New Series of Radical-Triplet Pair System : Modulation of Radical-Triplet Interaction by a Counter Ion

    L. Maretti; I. SM Saiful; T. Kajiwara; R. Miyamoto; Y. Ohba; S.Yamauchi

    2006年, Molecular Physics, 104, 1619 - 1626, doi

書籍等出版物

  • 錯体化学 有機・無機複合体の分子科学

    三共出版 (ISBN: 978-4-7827-0800-2 C3043)

講演・口頭発表等

  • Gd(III)錯体における遅い磁化緩和現象

    梶原孝志; 増田優花; 阪田潮実; 萱原早織; 入江夏生; 古府麻衣子; 河野洋平; 榊原俊郎

    希土類討論会, 2019年05月

  • トリスジピコリナトGd(III)単核錯体における遅い磁気緩和の発現

    上岡萌音; 上岡詩歩; 中西咲葵; 小川はる菜; 片岡悠美子; 梶原孝志

    日本化学会第99春季年会, 2019年03月, 甲南大学岡本キャンパス

  • トリスジピコリナトDy(III)単核錯体のSMM特性における対カチオン交換の効果

    上岡詩歩; 上岡萌音; 中西咲葵; 小川はる菜; 片岡悠美子; 梶原孝志

    日本化学会第99春季年会, 2019年03月, 甲南大学岡本キャンパス

  • Lanthanide-based Single Molecule Magnets - Correlation between the Molecular Structure and the Magnetic Anisotropy

    梶原孝志

    The 2nd International Symposium on Coordination Ionic Compounds, 2018年12月, true

  • Syntheses and SMM properties of Ln(III) complexes supported by an N5-Schiff base ligand

    梶原孝志

    International Conference on Coordination Chemistry, 2018, Sendai, 2018年08月, true

  • Sensing Ability of Luminescent Lanthanide Complexes for Anions Supported by Cyclen-based Ligands

    梶原孝志

    International Conference on Coordination Chemistry, 2018, Sendai, 2018年08月

  • Slow Magnetic Relaxation Properties of M(II)?Ln(III)?M(II)\nTrinuclear Complexes (Ln = Gd, Tb; M = Mg, Zn)

    梶原孝志

    International Conference on Coordination Chemistry, 2018, Sendai, 2018年08月

  • Syntheses, structures, and SMM behaviors of M-Ln(III)-M trinuclear complexes with threefold symmetry (Ln = Ce, Nd; M = Mg)

    梶原孝志

    International Conference on Coordination Chemistry, 2018, Sendai, 2018年08月

  • N5-Schiff塩基配位子をエカトリアルに持つ Ln(III)錯体の合成と単分子磁石特性

    小林 楓; 原田幸奈; 片岡悠美子; 梶原孝志

    日本化学会第98春季年会, 2018年03月, false

  • サイクレン骨格を有する発光性希土類錯体によるアニオン認識能の検討

    工藤真弓; 小森優美; 片岡悠美子; 梶原孝志

    日本化学会第98春季年会, 2018年03月, false

  • IDA骨格を基盤とする新規四座配位子を含むEu(III)錯体の水溶液中における錯体形成挙動と発光特性の検討(IDA:iminodiacetic acid)

    小森優美; 工藤真弓; 片岡悠美子; 梶原孝志

    日本化学会第98春季年会, 2018年03月, false

  • 希土類を基盤とする単分子磁石の設計と物性

    梶原孝志

    兵庫県立大学フロンティア機能物質創製センターシンポジウム, 2018年01月

  • Lanthanide-based single molecule magnets?design of the magnetic anisotropy

    梶原孝志

    One Day Symposium of Research Center for Structural Thermodynamics, 2017年12月

  • 三回対称性をもつMg(II)-Ln(III)-Mg(II)三核錯体(Ln = Ce, Nd)における磁気希釈が磁気特性に及ぼす効果

    阪田潮実; 増田優花; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志

    錯体化学会第67回討論会, 2017年09月, false

  • オキシ二酢酸を配位子としたLnIII単核錯体における遅い磁化緩和の発現

    中西咲葵; 小川はる菜; 片岡悠美子; 梶原孝志

    錯体化学会第67回討論会, 2017年09月, false

  • 直線状M(II)-Ln(III)-M(II)三核錯体の磁気特性に対して及ぼす因子の解明 (Ln = Gd, Tb, M= Mg, Zn)

    増田優花; 阪田潮実; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志

    錯体化学会第67回討論会, 2017年09月, false

  • 3回対称を持つLn(III)単分子磁石に対するプロトン化の効果

    小川はる菜; 中西咲葵; 片岡悠美子; 梶原孝志

    錯体化学会第67回討論会, 2017年09月, false

  • 三回対称性をもつMg(II)?Ln(III)?Mg(II)三核錯体 (Ln = Ce, Pr, Nd)の合成と構造および磁気特性の比較

    阪田潮実; 増田優花; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志

    日本化学会第97春季年会, 2017年03月, false

  • 直線状TM(II)?Tb(III)?TM(II)三核錯体において反磁性金属イオンがTb(III)イオンの遅い磁化緩和に及ぼす効果 (TM(II) = Mg(II),Zn(II),Cd(II))

    増田優花; 阪田潮実; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志

    日本化学会第97春季年会, 2017年03月, false

  • 分子サイズの磁石を作る~分子磁性体の仕組みと設計 Syntheses of Molecular-based Magnets ? Designing of Magnetic Anisotropy ?

    梶原孝志

    日本希土類学会第34回講演会, 2016年11月, false

  • 分子磁性体の最近の話題~d金属とf金属の違いを中心に

    梶原孝志

    錯体化学若手の会 第55回 近畿支部 勉強会, 2016年11月, false

  • Synthesis and Single Molecule Magnet behavior of linear Zn(II)-Tb(III)-Zn(II) trinuclear complex which possesses three-fold symmetry

    梶原孝志

    ICMM2016 The 15th International Conference on Molecule-Based Magnets, 2016年09月, true

  • Syntheses, structures, and SMM behaviors of a Zn(II)-Ce(III)-Zn(II)complexes with threefold symmetry

    梶原孝志

    ICMM2016 The 15th International Conference on Molecule-Based Magnets, 2016年09月, true

  • Slow magnetic relaxation behaviors of Ln(III) complexes which belong to the D3 point group

    梶原孝志

    ICMM2016 The 15th International Conference on Molecule-Based Magnets, 2016年09月, true

  • Syntheses and SMM behaviors of prolate-type Ln(III) mononuclear complexes which belong to the D3 point group

    梶原孝志

    ICMM2016 The 15th International Conference on Molecule-Based Magnets, 2016年09月, true

  • 結晶学的に三回対称を持つZn(II)-Ln(III)-Zn(II)三核錯体の合成と単分子磁石特性

    萱原早織; 入江夏生; 片岡悠美子; 梶原孝志; 山村朝雄

    錯体化学会第66回討論会, 2016年09月, false

  • 三回対称を持つCe(III)単分子磁石の合成と磁気特性の比較

    入江夏生; 萱原早織; 片岡悠美子; 梶原孝志; 山村朝雄

    錯体化学会第66回討論会, 2016年09月, false

  • 溶液中での五配位座Pybox誘導体を用いたEu(III)錯体の構造と発光特性の相関

    野上実沙; 中村香穂; 片岡悠美子; 篠田哲史; 梶原孝志

    錯体化学会第66回討論会, 2016年09月, false

  • Pybox配位子を含むEu(III)/Tb(III)混合希土類錯体による発光性アニオンセンシング

    中村香穂; 野上実沙; 片岡悠美子; 篠田哲史; 梶原孝志

    錯体化学会第66回討論会, 2016年09月, false

  • 点群D3の対称性を持つLn(III)単核錯体における遅い磁化緩和の発現

    中西咲葵; 小川はる菜; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志; 山村朝雄

    錯体化学会第66回討論会, 2016年09月, false

  • 3回対称を持つLn(III)単分子磁石に対する側鎖導入の効果

    小川はる菜; 中西咲葵; 萱原早織; 入江夏生; 片岡悠美子; 梶原孝志; 山村朝雄

    錯体化学会第66回討論会, 2016年09月, false

  • Single Molecule Magnet behaviors of isostructural Zn(II)-Ln(III)-Zn(II) tri-nuclear complexes (Ln = Ce, Nd, Tb, and Dy)

    梶原孝志

    Rare Earths 2016 in Sapporo, 2016年06月, Sapporo, Japan, true

  • Syntheses and Single Molecule Magnet Behaviors of Linear Zn(II)-Ln(III)-Zn(II) Trinuclear Complexes which Possess Pseudo Three-fold Symmetry (Ln = Tb, Dy)

    梶原孝志

    Rare Earths 2016 in Sapporo, 2016年06月, Sapporo, Japan, true

  • 点群D3の対称性を持つLn(III)単核錯体における遅い磁化緩和の発現

    中西 咲葵; 小川はる菜; 萱原 早織; 入江 夏生; 片岡悠美子; 梶原 孝志; 山村 朝雄

    日本化学会第96春季年会, 2016年03月, false

  • 点群D3の対称性を持つYb(III)単核錯体の合成とSMM特性

    小川はる菜; 中西 咲葵; 萱原 早織; 入江 夏生; 片岡悠美子; 梶原 孝志; 山村 朝雄

    日本化学会第96春季年会, 2016年03月, false

  • 擬似的な三回対称を持つ直線状Zn(II)-Ln(III)-Zn(II)三核錯体の合成とSMM特性 (Ln = Tb, Dy)

    萱原 早織; 入江 夏生; Then Poh Ling; 竹原 千賀; 片岡 悠美子; 梶原 孝志; 山村 朝雄

    日本化学会第96春季年会, 2016年03月, false

  • SMM behaviors of isostructural Zn(II)-Ln(III)-Zn(II) tri-nuclear complexes (Ln = Ce, Nd, Tb, and Dy)

    梶原孝志

    The International Chemical Congress of Pacific Basin Societies 2015, 2015年12月, true

  • Syntheses and SMM behaviors of linear ZnII - LnIII - ZnII trinuclear complexes with pseudo threefold symmetry\n(Ln = Pr, Nd)

    梶原孝志

    The International Chemical Congress of Pacific Basin Societies 2015, 2015年12月, true

  • Luminescence Anion Sensing with Mixed-Ln(III) Complex containing Tridentate Pybox Ligand

    梶原孝志

    The International Chemical Congress of Pacific Basin Societies 2015, 2015年12月, true

  • Syntheses and Luminescence Properties of Ln(III) Complexes containing Pentadentate Pybox Derivative

    梶原孝志

    The International Chemical Congress of Pacific Basin Societies 2015, 2015年12月, true

  • Syntheses and SMM behaviors of lanthanide(III) azacrown-ether complexes; correlation between magnetic\nbehaviors and crystal structures

    梶原孝志

    The International Chemical Congress of Pacific Basin Societies 2015, 2015年12月, true

  • 結晶学的に三回対称を持つZn(II)-Ln(III)-Zn(II)三核錯体の合成と単分子磁石特性

    萱原早織; 入江夏生; 片岡悠美子; 梶原孝志; 山村朝雄

    錯体化学会第66回討論会, 2015年09月, false

  • 多座キレート配位子を用いたEr(III)単分子磁石合成の試み

    大岡彩加; 和田寿沙美; Then Poh Ling; 梶原孝志; 片岡悠美子; 山村朝雄

    錯体化学会第65回討論会, 2015年09月, false

  • Pybox誘導体を用いた希土類錯の構造と発光特性相関について

    原井麻希; 友塚育美; 中村香穂; 野上実沙; 片岡悠美子; 篠田哲史; 梶原孝志

    錯体化学会第65回討論会, 2015年09月, false

  • 擬似的な三回対称を持つ直線状Zn(II)-Ln(III)-Zn(II) 三核錯体の合成とSMM特性 (Ln = Pr, Nd)

    萱原早織; 入江夏生; 大岡彩加; 和田寿沙美; 竹原千賀; 片岡悠美子; 梶原孝志; 山村朝雄

    日本化学会第95春季年会, 2015年03月, false

  • 擬似的な三回対称を持つ直線状Zn(II)-Ce(III)-Zn(II) 三核錯体の合成と構造、およびSMM特性の比較

    入江夏生; 萱原早織; 和田寿沙美; 大岡彩加; 竹原千賀; 片岡悠美子; 梶原孝志; 山村朝雄

    日本化学会第95春季年会, 2015年03月, false

  • Ln(III) azacrown-ether錯体の合成と単分子磁石特性; 磁気特性と\n結晶構造の相関

    和田寿沙美; 大岡彩加; 竹原千賀; Then Poh Ling; 片岡悠美子; 梶原孝志; 山村朝雄; 中野元裕

    日本化学会第95春季年会, 2015年03月, false

  • 五配座Pybox誘導体を含むEu(III) / Tb(III)錯体におけるアニオン依存の発光応答性

    野上実沙; 中村香穂; 友塚育美; 原井麻希; 片岡悠美子; 梶原孝志

    日本化学会第95春季年会, 2015年03月, false

  • クラウン骨格を有するPybox配位子を含むEu(III)錯体によるアニオン-カチオン認識

    友塚育美; 原井麻希; 中村香穂; 野上実沙; 片岡悠美子; 梶原孝志

    日本化学会第95春季年会, 2015年03月, false

  • Pybox配位子を含むEu(III)-Tb(III)混合錯体によるマルチアニオンセンシング

    中村香穂; 野上実沙; 友塚育美; 原井麻希; 片岡悠美子; 梶原孝志

    日本化学会第95春季年会, 2015年03月, false

  • 軽希土類を基盤とする単分子磁石

    梶原孝志

    第2回東北大学研究会プログラム 「金属錯体の固体物性最前線‐金属錯体と固体物性物理と生物物性の連携新領域をめざして‐」, 2015年02月, false

  • 希土類単分子磁石における磁化緩和の詳細な解析

    梶原孝志

    アルファ放射体実験室・基盤研究(S)(価数不安定性をもつアクチノイド化合物)合同研究会, 2015年02月, false

  • 軽希土類単分子磁石の合成と磁気特性の比較

    竹原千賀; Then Poh Ling; 梶原孝志; 片岡悠美子; 中野元裕; 山村朝雄

    錯体化学会第64回討論会, 2014年09月, false

  • Syntheses and Luminescence Properties of LN(III) Complexes with Pybox Derivatives

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • Syntheses and Luminescence Properties of Lanthanide complexes with Pyboc Ligands Connected to 15-crown-5-ether Moiety

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • Synthesis and SMM Behavior of Cerium(III) Crown-ether Complex

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • Syntheses and SMM Behaviors of Ln(III) Crown-ether Compelxes

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • Syntheses and Magnetic Properties of Cerium(III)-SMMs

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • Syntheses and SMM Behaviours of Linear Zn(II)-Dy(III)-Zn(II) Trinuclear Complexes

    梶原孝志

    41st International Conference on Coordination Chemistry, 2014年07月, true

  • 15-クラウン-5-エーテル骨格を有するPybox配位子を含む希土類錯体の合成と発光特性

    友塚育美; 原井麻希; 片岡悠美子; 梶原孝志

    日本化学会第94春季年会, 2014年03月, false

  • Pybox誘導体を用いたLn(III)錯体の合成と発光特性

    原井麻希; 友塚育美; 片岡悠美子; 梶原孝志

    日本化学会第94春季年会, 2014年03月, false

  • Ln(III) crown-ether錯体の合成とSMM特性

    大岡彩加; 和田寿沙美; 竹原千賀; Then Poh Ling; 片岡悠美子; 梶原孝志; 中野元裕; 山村朝雄

    日本化学会第94春季年会, 2014年03月, false

  • Ce(III) crown-ether錯体の合成とSMM特性

    和田寿沙美; 大岡彩加; 竹原千賀; Then Poh Ling; 片岡悠美子; 梶原孝志; 山村朝雄

    日本化学会第94春季年会, 2014年03月, false

  • 希土類単分子磁石の設計と遅い磁化緩和の観測

    梶原孝志

    第1回東北大学リーディング大学院研究会プログラム 「金属錯体の固体物性最前線‐金属錯体と固体物性物理と生物物性の連携新領域をめざし\nて‐」, 2014年02月, false

  • 希土類錯体の特異な磁気特性

    梶原孝志

    アルファ放射体実験室・基盤研究(S)(価数不安定性をもつアクチノイド化合物)合同研究会, 2014年02月, false

  • 単分子磁石Zn(II)-Dy(III)-Zn(II)直線状三核錯体における非常に遅い磁化緩和

    梶原孝志; 山下 桂; 片岡悠美子; 中野元裕; 山村朝雄

    錯体化学会第63回討論会, 2013年11月, false

  • Ce(III)単分子磁石の合成と磁気特性の詳細

    竹原千賀; 日野志織; Then Poh Ling; 梶原孝志; 片岡悠美子; 中野元裕; 山村朝雄

    錯体化学会第63回討論会, 2013年11月, false

  • 直線状Zn(II)-Dy(III)-Zn(II)三核錯体の合成とSMM特性の比較

    Then Poh Ling; 竹原千賀; 山下 桂; 梶原孝志; 片岡悠美子; 中野元裕; 山村朝雄

    錯体化学会第63回討論会, 2013年11月, false

  • 水溶液中で発光性を示すTripod型配位子を有する希土類錯体の錯体形成挙動と発光特性

    片岡悠美子; 川尻彩加; 川森紗由美; 篠田哲史; 梶原孝志

    錯体化学会第63回討論会, 2013年11月, false

  • Syntheses and magnetic properties of Ce(III)-SMMs

    梶原孝志

    The 2nd Japan-France Coordination Chemistry Symposium 2013, 2013年11月, true

  • Syntheses and SMM Behaviours of Linear Zn(II)-Dy(III)-Zn(II) Trinuclear Complexes

    梶原孝志

    The 2nd Japan-France Coordination Chemistry Symposium 2013, 2013年11月, true

  • 直線状Zn(Ⅱ)-Ce(Ⅲ)-Zn(Ⅱ)三核錯体の合成、構造とSMM挙動の発現

    竹原千賀; Then Poh Ling; 山下桂; 片岡悠美子; 梶原孝志; 中野元裕; 山村朝雄

    第93春季年会, 2013年03月

  • Zn(II)-Tb(III)-Zn(II)単分子磁石の構造制御と磁気特性の相関

    Then Poh Ling; 竹原千賀; 山下桂; 片岡悠美子; 梶原孝志; 中野元裕; 山村朝雄

    第93春季年会, 2013年03月, false

  • 中性子散乱による希土類単分子磁石のスピンダイナミクスの研究III

    古府麻衣子; 梶原孝志; 中野元裕; 中島健次; Giovanna Simeoni; nJason Gardner; Madhusudan Tyagi; 山室修

    日本物理学会 第68回年次大会, 2013年03月

  • LnZn, LnZn2, and LnZ3 Complexes as Single-Molecule Magnets

    梶原孝志

    40th International Conference on Coordination Chemistry, 2012年09月, Valencia, Spain

  • Single-Molecule-Magnet behaviors of linear Zn(II)-Ln(III)-Zn(II) complexes

    梶原孝志

    40th International Conference on Coordination Chemistry, 2012年09月, Valencia, Spain

  • Molecular Design of Zn (II)n ?Ln(III) Multinuclear Complexes and Their Luminescence Properties

    梶原孝志

    40th International Conference on Coordination Chemistry, 2012年09月, Valencia, Spain

  • 直線状Zn(II)-Tb(III)-Zn(II)三核錯体の磁気特性の詳細の解明

    山下桂; 宮崎理恵; 片岡悠美子; 梶原孝志; 中西貴之; 長谷川靖哉; 中野元裕; 山村朝雄

    第62回錯体化学討論会, 2012年09月, false

  • Zn(II)n-Ln(III)複核錯体によるアニオン応答性の希土類発光挙動

    片岡悠美子; 楠 尚子; 山下愛花; 中西貴之; 長谷川靖哉; 梶原孝志

    第62回錯体化学討論会, 2012年09月, false

  • 直線状Zn(II)-Ln(III)-Zn(II)三核骨格を基盤とする単分子磁石合成の軽希土類への展開

    梶原孝志; 日野詩織; 前田萌絵; 山下 桂; 片岡悠美子; 中野元裕; 山村朝雄

    第62回錯体化学討論会, 2012年09月, false

  • Structural Control of the Magnetic Anisotropy of Lanthanide-based SMMs

    梶原孝志

    62nd Fujihara Seminar, 2012年05月, The Fujihara Foundation of Science, Sendai, Japan, false

担当経験のある科目(授業)

  • 実践化学英語I (奈良女子大学)

  • ナノ金属錯体物性論演習 (奈良女子大学)

  • 機能性材料化学セミナーA-Ⅰ (奈良女子大学)

  • 機能性錯体化学セミナーⅠ (奈良女子大学)

  • ナノ金属錯体物性論 (奈良女子大学)

  • 機器分析法Ⅳ (奈良女子大学)

  • 機器分析法Ⅲ (奈良女子大学)

  • 機能性無機錯体化学Ⅰ (奈良女子大学)

  • 無機化学概論Ⅰ (奈良女子大学)

  • 卒業研究IV (奈良女子大学)

  • 卒業研究III (奈良女子大学)

  • 無機化学外国語特論Ⅰ (奈良女子大学)

  • 機能化学概論 (奈良女子大学)

  • 化学基礎実験1 (奈良女子大学)

  • 無機化学入門 (奈良女子大学)

  • 化学特別研究II (奈良女子大学)

  • 卒業研究2 (奈良女子大学)

  • 化学セミナー2 (奈良女子大学)

  • 機能性無機錯体化学I (奈良女子大学)

  • 化学特別研究I (奈良女子大学)

  • 卒業研究1 (奈良女子大学)

  • 化学セミナー1 (奈良女子大学)

  • 化学特別研究IV (奈良女子大学)

  • 化学セミナー4 (奈良女子大学)

  • 卒業研究4 (奈良女子大学)

  • エネルギーと化学 (奈良女子大学)

  • 機器分析法II (奈良女子大学)

  • 化学特別研究III (奈良女子大学)

  • 機能性錯体化学セミナーI (奈良女子大学)

  • 化学セミナー3 (奈良女子大学)

  • 卒業研究3 (奈良女子大学)

  • 化学専門実験1 (奈良女子大学)

  • 奈良女子大の化学 (奈良女子大学)

  • サイエンスオープンラボIC (奈良女子大学)

  • サイエンスオープンラボIIC (奈良女子大学)

  • 材料科学 (奈良女子大学)

  • 機器分析法2 (奈良女子大学)

  • 固体化学 (奈良女子大学)

  • 遷移元素の化学 (奈良女子大学)

  • 機能性材料科学 (奈良女子大学)

所属学協会

  • 日本化学会

  • 錯体化学会

  • 分子科学会

  • 日本希土類学会

  • American Chemical Society

Works(作品等)

  • f金属錯体における特異な磁気特性の詳細の解明

    2013年04月 - 2016年03月

  • f金属錯体の磁気異方性制御

    2010年04月 - 2013年03月



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