Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1107/S2414314618012361

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

A molecular salt with a bulky cation and anion, (H2bipip)-(H)2[Fe(CN)6] (1) (H2bipip2+: 4,4¤-bipiperidine-1,1¤-diium), has been prepared. The salt comprises protons (H+) as counter cations. Single-crystal X-ray structure analysis revealed that the proton is trapped between two cyanido ligands of [Fe(CN)6]41 anions, forming a very short N£H+£N hydrogen bond.

DOI： 10.1246/cl.180157

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

The [{Fe(Me3tacn)}2(-P2O7)(-HPO4)]12H2O dinuclear Fe2(III, III) complex was prepared. The HPO4 2 bridge in the complex arises from hydrolysis of the pyrophosphate bound to the Fe(III) centers in the trinuclear [{Fe(Me3tacn)}3- (P2O7)2]+ intermediate. Electrochemical reduction of this complex at pH &lt
3.2 results in dissociation of the H2PO4 bridge.

DOI： 10.1246/bcsj.20170427

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A comparative study of van der Waals and ionic crystals can provide vital information for the medical and food industries. In this work, we investigated the coenzyme pyrroloquinoline quinone (PQQ), which contains three carboxyl groups coupled to imidazole, pyridine, and quinone. Whole-crystal analysis (crystal-ome) was attempted for Na(n)PQQ (n = 04) crystals. All deprotonation sites were found to be dependent on pK(a) except for the Na sites, which cannot be explained by pK(a). The Na(1)PQQ crystal exhibited an unusual ionic bond, forming COOH-Na+ at one of the carboxyl sites in the structure. The difference in the solubility of the van der Waals and ionic crystals was also investigated, with a focus on the dissolution processes of Na(0)PQQ and Na(2)PQQ, by combining molecular dynamics simulations with experiments that define the crystal surfaces. This study is the first step toward developing a general rule to link the different types of crystal structures with different dissolution mechanisms and rates.

DOI： 10.1021/acs.cgd.7b00324

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The methyl viologen dication, used under the name Paraquat as an agricultural reagent, is a well-known electron-acceptor species that can participate in chargetransfer (CT) interactions. The determination of the crystal structure of this species is important for accessing the CT interaction and CT-based properties. The title hydrated salt, bis(1,1'-dimethyl-4,4'-bipyridine-1,1'-diium) hexacyanidoferrate(II) octahydrate, (C12H14N2)(2)[Fe(CN)(6)]center dot 8H(2)O or (MV)(2) [Fe(CN)(6)]center dot 8H(2)O [M (2+) is the 1,1'-dimethyl-4,4'-bipyridine-1,1'-diium (methyl viologen) dication], crystallizes in the space group P21/c with one MV2+ cation, half of an [Fe(CN)(6)](4-) anion and four water molecules in the asymmetric unit. The Fe II atom of the [Fe(CN)(6)](4-) anion lies on an inversion centre and has an octahedral coordination sphere defined by six cyanide ligands. The MV2+ cation is located on a general position and adopts a noncoplanar structure, with a dihedral angle of 40.32 (7)degrees between the planes of the pyridine rings. In the crystal, layers of electron-donor [Fe(CN)(6)](4-) anions and layers of electronacceptor MV2+ cations are formed and are stacked in an alternating manner parallel to the direction of the -2a + c axis, resulting in an alternate layered structure.

DOI： 10.1107/S2053229617007616

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The PtII atom in the title compound, [PtCl2{(C6H4)(NH2)2}], lies on a twofold rotation axis and has a slightly distorted square-planar coordination environment defined by two N atoms of an 1,2-phenylenediamine ligand and two Cl- ions. In the crystal, the planar complex molecules are stacked parallel to the c axis, resulting in a columnar structure. In a column, an infinite almost straight Pt·Pt chain is formed, suggesting weak metal-metal interactions [Pt·Pt = 3.3475 (8) Å]. The crystal packing is stabilized by a three-dimensional N-H·Cl hydrogen-bonding network between the amino groups and the Cl ligands of adjacent molecules.

DOI： 10.1107/S2056989017008477

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1107/S2414314617003820

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DOI： 10.1107/S2414314617001444

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The title salt, catena-poly[[[bis(ethylenediamine)platinum(II)]-μ-bromido-[bis(ethylenediamine)platinum(IV)]-μ-bromido] tetrakis(2-bromoethanesulfonate) dihydrate], {[PtIIPtIV Br2(C2H8N2)4]C2H4BrSO3)4·2H2O}n, crystallizes in the space group P21212. It has a linear chain structure extending parallel to the c axis, composed of square-planar [Pt(en)2]2+ and elongated octahedral trans-[PtBr2(en)2]2+ cations (en is ethylenediamine) stacked alternately and bridged by the Br atoms. The Pt site of the [PtII/IV(en)2] unit is located on a general position. The Br site, which is also located on a general position, is equally disordered over two positions. The Pt and Br atoms form a slight zigzag ⋯Br - PtIV - Br⋯PtII⋯ chain, with PtIV - Br bond lengths of 2.453 (2) and 2.491 (3) Å, PtII⋯Br contacts of 3.069 (2) and 3.032 (3) Å, and PtIV- Br⋯PtIIangles of 178.06 (13) and 177.70 (13)°. The mixed-valence state of the Pt site is expressed by the parameter δ = (PtIV-Br)/(PtII⋯Br), with values of 0.799 and 0.822 for the two independent Br atoms. In the crystal, N - H⋯O and O - H⋯O hydrogen bonds between the amine groups of the Pt complex chains, the sulfonate groups and water molecules of crystallization, stabilize the cationic columnar structure.

DOI： 10.1107/S2056989017009598

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The title compound, (C7H10N)2(H3O)2[Fe(CN)6] or (Etpy)2(H3O)2[Fe(CN)6] (Etpy+ is 1-ethylpyridinium), crystallizes in the space group Pnnm. The FeII atom of the [Fe(CN)6]4- anion lies on a site with site symmetry..2/m, and has an octahedral coordination sphere defined by six cyanido ligands. Both the Etpy+ and the oxonium cations are located on a mirror plane. In the crystal, electron-donor anions of [Fe(CN)6]4- and electron-acceptor cations of Etpy+ are each stacked parallel to the b axis, resulting in a columnar structure with segregated moieties. The crystal packing is stabilized by a three-dimensional O - H⋯N hydrogen-bonding network between the oxonium ions and the cyanide ligands of [Fe(CN)6]4-.

DOI： 10.1107/S2056989017000810

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We prepared a new Ru-2(III, IV) complex containing a pyrophosphate as the dinucleating component, by the reaction between the mononuclear complex [Ru(Me(3)tacn)Cl-3] and Na4P2O7 center dot 10H(2)O in aqueous solution. Cyclic voltammetric measurement for the complex [{Ru(Me(3)tacn)}(2)(mu-O)(mu-P2O7)]PF6 (1) in aqueous solution revealed the formation of two species with higher oxidation states, such as [O=Ru(IV)Ru(IV)=O] and [O=Ru(IV)Ru(V)=O](+). Furthermore, this complex showed activity for water oxidation reaction with Ce(NH4)(2)(NO3)(6) as the chemical oxidant in acidic aqueous solution.

DOI： 10.1246/cl.160721

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The title compound, catena-poly[[[bis(ethylenediamine-kappa N-2,N')platinum(II)]-mu-chlorido-[bis(ethylenediamine)platinum(IV)]-mu-chlorido] tetrakis{4-[(4-hydroxyphenyl)diazenyl]benzenesulfonate} dihydrate], {[(PtPtCl2)-Pt-II-Cl-IV(C2H8N2)(4)](HOC6H4N=NC6H4SO3)(4)center dot 2H(2)O}(n), has a linear chain structure composed of square-planar [Pt(en)(2)](2+) (en is ethylenediamine) and elongated octahedral trans-[PtCl2(en)(2)](2+) cations stacked alternately, bridged by Cl atoms, along the b axis. The Pt atoms are located on an inversion centre, while the Cl atoms are disordered over two sites and form a zigzag center dot center dot center dot Cl-Pt-IV-Cl center dot center dot center dot Pt-II center dot center dot center dot chain, with a Pt-IV-Cl bond length of 2.3140 (14) angstrom, an interatomic Pt-II center dot center dot center dot Cl distance of 3.5969 (15) angstrom and a Pt-IV-Cl center dot center dot center dot Pt-II angle of 170.66 (6)degrees. The structural parameter indicating the mixed-valence state of the Pt atom, expressed by delta = (Pt-IV-Cl)/(Pt-II center dot center dot center dot Cl), is 0.643.

DOI： 10.1107/S2053229615019877

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The structure of the title compound, which represents a mixed-valence platinum(II,IV) complex, {[PtIIPtIVI2(C2H8N2)4][CH3(CH2)7SO3]4·2H2O} n , has been redetermined in a different space group. In contrast to the previously reported determination in the space group P21 cn [Matsushita &amp
Taira (1999). Synth. Met. 102, 1787-1788], the current model was refined in the centrosymmetric space group Pmcn using the original diffraction data. The title compound has a linear chain structure composed of square-planar [Pt(en)2]2+ and elongated octahedral trans-[PtI2(en)2]2+ cations (en is ethylenediamine) stacked alternately, bridged by the I atoms, parallel to the c axis. Inorganic layers aligned parallel to the bc plane, composed of the Pt-complex columns, the -SO3 - part of the octane-1-sulfonate anion, and the water molecule of crystallization, are stacked alternately with organic layers composed of the long-chain alkyl groups along the a axis. The Pt and I sites are located on the same mirror plane whereby the I site is equally disordered over two positions. The Pt and I atoms form a slight zigzag ⋯I - PtIV - I⋯PtII⋯ chain, with PtIV - I bond lengths of 2.6888(17) and 2.7239(17)Å, PtII⋯I contacts of 3.2065(17) and 3.1732(16)Å, and PtIV - I⋯PtII angles of 178.3(3) and 176.7(2)°. The mixed-valence state of the Pt site is expressed by the structural parameter δ = (PtIV - I)/(PtII⋯I), with values of 0.839 and 0.858 for the two independent I atoms. In the crystal, N - H⋯O hydrogen bonds involving the cationic chains, the sulfonate groups and water molecules of crystallization, stabilize the columnar structure.

DOI： 10.1107/S2056989015016801

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For fabricating photoresponsive multifunctional materials, we have developed the potassium salt of a new anionic spiropyran, 1',3',3'-trimethyl-6-nitrospiro [2H-1-benzopyran-2,2'-indoline]-5'-sulfonate (1(-)), with the sulfonate group present on the indoline moiety and whose crystal structure was revealed by single-crystal X-ray diffraction analysis. The photochromism of 1.K was demonstrated at room temperature in the KBr-diluted state, as well as in solution. The protonated spiropyran 1H shows negative photochromism.

DOI： 10.1246/cl.130904

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Electronic excitation spectra of cis-platin (cis-[(PtCl2)-Cl-II(NH3)(2)]), which is a well-known antitumor drug, and trans-platin (trans-[(PtCl2)-Cl-II(NH3)(2)]) were experimentally observed and theoretically analyzed using ab initio spin-orbit CASPT2 (SO-CASPT2) calculations. Cis-platin showed two series of absorption bands in the wavelength regions of 250-350 nm and 350-450 nm. On the other hand, trans-platin showed three series of absorption bands in the wavelength regions of 260-280 nm, 300-340 nm and 360-400 nm. Comparing SO-CASPT2 calculations at the optimum structures in gas-phase conditions with those in DMF solvent, which were obtained by PCM implicit solvation model, it was clarified that both spin-orbit effect and solvent effect cannot be negligible even for quantitative assignments of electronic excitation spectra of cis/trans-platin. (c) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molstruc.2012.11.027

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE BV  

Excitation photon energy dependence of the relaxation processes of the photoexcited states in a quasi-one-dimensional halogen-bridged platinum complex has been investigated by femto second transient absorption measurements. In a Pt complex, [Pt(en)(2)][Pt(en)(2)I-2](SO4)(2)center dot 6H(2)O (Pt-I-SO4), a photo-induced absorption (PA) band caused by self trapped excitons (STE's) has been observed when the excitation photon energy is close to the peak energy, 1.44eV, of the absorption band of the one photon allowed charge transfer (CT) exciton with odd parity. In addition, a long lived PA bands caused by charged solitons (CS's) has been observed. The intensity of these long lived CS absorption band shows quadratic excitation power dependence. This shows that CS's pairs are not generated from odd-CT-excitons but from the higher energy two photon excited states. When the excitation photon energy is close to a half of the of the even CT-exciton energy, 1.84eV, PA bands caused by STE's and CS's have been observed. These states are generated from the two photon excited even CT-excitons. When the excitation photon energy is much higher than the energy of the odd CT-exciton, PA bands caused by CS's and polarons have been observed. The intensities of these PA bands show linear excitation power dependences. Photo-generated free electron hole pairs are considered to relax into CS's and polarons. (C) 2011 Published by Elsevier B. V.

DOI： 10.1016/j.phpro.2011.02.016

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Two-photon absorption spectra of an MX-chain compound [Pt(en)(2)][Pt(en)(2)I-2[SO4)(2)- 6H(2)O have been measured. The two-photon absorption coefficient at the peak energy of the two-photon absorption band has been found to be 1.3 x 10(3) cm/GW. This value is two orders of magnitude larger than that predicted by the gap-dependent scaling law derived for conventional semiconductors and larger than the value that has been reported in polydiacetylenes. Electro-reflectance spectra have been measured and analyzed by a three-level model. The large two-photon absorption coefficient can be explained in the framework of the model. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jlumin.2007.11.045

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We display that a tetracyanoplatinate(II) forming a charge-transfer complex with methyl viologen dication in the crystal exhibits intense luminescence despite no direct Pt center dot center dot center dot Pt interaction.

DOI： 10.1246/cl.2008.398

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

We performed the single-crystal X-ray diffraction study of a perovskite-type gold mixed-valence compound, (Cs2AuAuCl6)-Au-I-Cl-III, under high pressures up to 18 GPa by using a dianiond-anvil-cell with helium gas as Lin ideal hydrostatic press ure-transmitting medium. The lattice parameters and the variable atomic positional parameters were obtained with reasonable accuracy at various pressures. A structural phase transition at ca. 12.5GPa from I4/mmm to Pm3m was found. The lattice parameters a() and ca, denoted in the tetragonal cell setting, result in the relationship 2 (1/2)(10 = co. and the superstructure reflections h k I (I is odd), caused by the shift of the Cl ions from the midpoint of the An ions, disappeared at pressures above the phase transition. Both elongated [(AuCl6)-Cl-III] and compressed [(AuCl6)-Cl-I] octahedra in the low-pressure phase smoothly approach regular octahedra with increasing pressure. Above the structural phase transition at 12.5GPa, all the [AuCl6] Octahedra are crystallographically equivalent, which shows that the tetragonal-to-cubic phase transition accompanies the valence transition from the Au-I/Au-III mixed-valence state to the Au-II single-valence state. (C) 2007 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2007.01.037

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The results are reported of the pressure (P) dependence of the electrical resistance (R), the thermoelectric power (Seebeck effect) (S), and compressibility as well as the time dependence of R at fixed P up to 20 GPa for four metallo-organics based on the BEDT-TTF (bisethylenedithiolo-tetrathiofulvalene) group, theta-(BEDT-TTF)(2)CsZn(SCN)(4), alpha-(BEDT-TTF)(2)I-3, beta'-(BEDT-TTF)(2)PF6, and (BEDT-TTF)-TCNQ. X-ray powder and single-crystal diffraction studies were also made on theta-(BEDT-TTF)(2)CsZn(SCN)(4) at high pressures up to P similar to 10 GPa. The R values of all the crystals decreased with pressure up to P similar to 3-5 GPa (low-pressure regime), and then the sign of dR/dP inverted (high-pressure regime). From the investigation of the mechanical and structural properties, these materials were found to have a large compressibility in the low-pressure regime, and a small one in the high-pressure region. In theta-(BEDT-TTF)(2)CsZn(SCN)(4) we observed pressure-induced reversible degradation (amorphization) in structure without a solid-phase reaction. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/pssb.200672530

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A platinum complex with a non-innocent ligand, [Pt-II(L)(2)] (1), where L is o-semibenzoquinonediimine mono-anion, has two polymorphs. In one polymorph, molecules related by translation are arranged in the same orientation along the c axis, while in the other, molecules related by a c-glide plane are aligned alternately in different orientation.

DOI： 10.1246/bcsj.79.1237

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pH-Dependent color changes of an innocent diamineplatinum(II) complex, [Pt(H2L)(2)]Cl-2 ([1]Cl-2)), where H2L is o-phenylenediamine, and the pH-dependent redox of non-innocent diimineplatinum(II) complexes, [Pt(L)21 (2) and [[Pt(L)(2)}(2)]Cl-2 ([2(2)]Cl-2), where L is o-semibenzoquinonediimine monoanion or neutral o-benzoquinonediimine, have been investigated by vis-NIR spectroscopy and cyclic voltammetry in solutions of various pH. The crystals of [1]Cl-2. 2H(2)O and [2(2)]Cl-2.6H(2)O have also been characterized by X-ray crystallography. [1]Cl-2 in an aqueous solution changes from colorless either to purple or to yellow-green depending on the pH of the solution. The purple solution gave a neutral complex 2 and the yellow-green solution yielded [2(2)]Cl-2.6H(2)O. In the latter complex, the monocation, [2](+), dimerizes forming a weak Pt-Pt bond [3.0109(4) angstrom] with no bridging ligands. The spectroscopy of [1]Cl-2 in the buffer solutions shows that the complex 2 is formed in the range of pH 4.6-5.8, while the complex [2](+) is generated in the range of pH 2.1-4.5. These results indicate that the one-electron redox process of [2](+)/2 depends on the pH of the solution. By adjusting the pH of the solution by adding acid or base, it is possible to reversibly control this redox process. This behavior is a kind of pH-dependent chromism because of their color being different.

DOI： 10.1246/bcsj.79.1046

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

The title compound, {[(PtPtI2)-Pt-II-I-IV(C2H8N2)(4)](HPO4)(H2PO4)I center dot 3H(2)O}(n), has a chain structure composed of square-planar [Pt(en)(2)](2+) and elongated octahedral trans-[PtI2(en)(2)](2+) cations (en is ethylenediamine) stacked alternately along the c axis and bridged by the I atoms; a three-dimensionally valence-ordered system exists with respect to the Pt sites. The title compound also has a unique cyclic tetramer structure composed of two hydrogenphosphate and two dihydrogenphosphate ions connected by strong hydrogen bonds [O center dot center dot center dot O = 2.522 (10), 2.567 (10) and 2.569 (11) angstrom]. The Pt and I atoms form a zigzag center dot center dot I-Pt-IV-I center dot center dot Pt(II)center dot center dot center dot chain, with Pt IV-I bond distances of 2.6997 (7) and 2.6921 (7) angstrom, interatomic Pt(II)center dot center dot center dot distances of 3.3239 (8) and 3.2902 (7) angstrom, and Pt-IV-I center dot center dot Pt-II angles of 154.52 (3) and 163.64 (3)degrees. The structural parameters indicating the mixed-valence state of platinum, expressed by delta = (Pt-IV-I)/(Pt-II-I), are 0.812 and 0.818 for the two independent I atoms.

DOI： 10.1107/S0108270105041247

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Under pressures as high as 20 GPa at room temperature the electronic and structural properties of organic conductors were measured to search for interesting pressure regimes where novel electronic states were expected. Thermopower, two-probe electrical resistance and contraction of sample's volume were measured on the organic conductors: theta-(BEDT-TTF)(2)CsZn(SCN)(4), alpha-(BEDT-TTF)(2)I-3, (BEDT-TTF)(2)PF6 and (BEDT-TTF)-TCNQ. All the materials exhibited a positive thermopower of the order of 10 mu V/K. At about 4-7 GPa (crossover pressure P-x) sharp changes were found in the pressure dependence of electronic and mechanical properties of all the substances under consideration related probably to the structural changes under pressure.

DOI： 10.1007/s10909-006-9126-7

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-V C H VERLAG GMBH  

Two photon absorption spectra of [Pt(en)(2)][Pt(en)(2)Br-2](SO4)(2)center dot 6H(2)O have been measured by the femtosecond transient absorption measurements. A two photon absorption band of an exciton with even parity has been found 0.8 eV above the one photon absorption band of an exciton with odd parity. The two photon absorption coefficient has been estimated at 1.5x10(2) cm/GW for pump energy of 1.56 eV and for probe energy of 1.95 eV at 100 K. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/pssc.200672160

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Rb-2[(AuI2)-I-I][(AuI4)-I-III], dirubidium diiodoaurate(I) tetraiodoaurate(III), has a tilted and distorted perovskite-type structure which is isotypic with its bromide analogue Rb-2[(AuBr2)-Br-I][(AuBr4)-Br-III]. The structure contains compressed and elongated [AuI6] octahedra tilted away from each other and stacked alternately along the [001], [110] and [110] directions by sharing all the corner I- ions.

DOI： 10.1107/S1600536805025432

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The structure of the title compound, {[(PtCl)-Cl-II/IV-(C2H8N2)(2)](PF6)(2)}(n) or [Pt-II(C2H8N2)(2)][(PtCl2)-Cl-IV(C2H8N2)(2)]-(PF6)(4), has been redetermined [Matsushita (1993). Synth. Met. 56, 3401 - 3406] from image-plate data. No superstructure was observed, in contrast to the situation in related compounds. The linear chain structure consists of square-planar [Pt(en)(2)](2+) and elongated octahedral trans[PtCl2(en)(2)](2+) cations (en is ethylenediamine) stacked alternately, bridged by the Cl atoms, along the b axis. The Pt atom is located on an inversion centre and the Cl atom ( site symmetry 2) is disordered over two sites, resulting in Pt-IV-Cl and Pt-II.........Cl bond distances of 2.327 (4) and 3.191 (4) angstrom, respectively. The delta structural parameter, indicating the mixed-valence state of the Pt atoms, is 0.729.

DOI： 10.1107/S1600536805017873

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The title compound, dicaesium gold( I) gold(III) hexabromide or dicaesium dibromoaurate( I) tetrabromoaurate( III), Cs-2[(AuBr2)-Br-I][(AuBr4)-Br-III], has a distorted perovskite-type structure which is isotypic with its chloride and iodide analogues, (Cs2AuAuX6)-Au-I-X-III ( X is Cl or I). The structure contains compressed and elongated [AuBr6] octahedra stacked alternately along the [ 001] and [ 110] directions by sharing all the corner Br- ions. The compound is also characterized by the assembly of the gold complex ions [(AuBr2)-Br-I](-) and [(AuBr4)-Br-III](-). Structural parameters indicating the mixed-valence distortion of Au-I and Au-III due to displacement of two crystallographically independent halide ( X) ions from the mid-point between the two adjacent Au ions, expressed by (Au-X)/((AuX)-X-...), are 0.738 ( 2) along the c axis and 0.799 ( 1) in the ab plane. These values show that the mixed-valence distortion of the title bromide is intermediate between those of the chloride and the iodide. The distortion of the title bromide from the cubic system to the tetragonal system, expressed by 2(1/2) a/c = 0.9704 ( 1), is also intermediate between those of the chloride and the iodide.

DOI： 10.1107/S1600536805016594

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The title compound, {[Pt2Cl2(C2H8N2)(4)](BF4)(4)}(n) or [Pt-II(C2H8N2)(2)][(PtCl2)-Cl-IV(C2H8N2)(2)](BF4)(4), has a linear chain structure composed of square-planar [Pt(en)(2)](2+) and elongated octahedral trans- [PtCl2(en)(2)](2+) cations (en is ethylenediamine) stacked alternately, bridged by the Cl atoms, along the c axis. The Cl atom bridging the adjacent Pt atoms is disordered over two sites along the ... Cl-Pt-IV-Cl...Pt-II... chain, which lies on a twofold axis. The Pt-IV-Cl and Pt-II...Cl bond distances are 2.319 (3) and 3.052 (3) Angstrom, respectively. A structural parameter indicating the mixed-valence state of the Pt atom, expressed by delta = (Pt-IV-Cl)/(Pt-II...Cl), is 0.760.

DOI： 10.1107/S1600536805004113

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Ultrafast relaxation processes of photoexcited states in a quasi-one-dimensional halogen-bridged mixed-valence metal complex [Pt(en)(2)][Pt(en)(2)I-2](SO4)(2).6H(2)O have been investigated by femtosecond transient absorption spectra measurements. A photoinduced absorption band caused by non-thermalized self-trapped excitons has been found. Oscillation of the absorption band caused by the symmetric Pt-I stretching mode of the self-trapped exciton with a frequency of 103 cm(-1) has been observed. The rise time of a polaron absorption band has been measured to be 1.2 ps. This corresponds to the decay time, 1.1 ps, of a photoinduced absorption band which oscillates with a frequency of 74 cm(-1). (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jlumin.2004.01.061

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(n-C3H7)(4)N[(FeFeIII)-Fe-II(dto)(3)] shows a new type of first order phase transition called chare-transfer phase transition around 120 K. where the charge transfer between Fe-II and Fe-III occurs reversibly. Recently, we have succeeded in obtaining single crystals of the title complex and determined the crystal Structure at room temperature. Crystal data: space group P6(3), a = 10.0618(5) Angstrom. c = 16.0424(7) Angstrom. V = 1406.54(12)Angstrom, Z = 2. Moreover. we have investigated the structural transition caused by the charge-transfer phase transition by means of powder X-ray diffraction measurement. When the temperature is decreased. the a-axis. which corresponds to the hexagonal ring size in two-dimensional honeycomb network structure of [Fe-II Fe-III(dto)(3)](infinity). contracts by 0.1 Angstrom at the charge-transfer transition temperature (T-CT) while the c-axis. perpendicular to the honeycomb network layer. elongates by 0.1 Angstrom at T-CT. Consequently, when the temperature is decreased, the unit cell volume decreases without noticeable anomaly around T-CT, which is responsible for the quite sniall vibrational contribution to the entropy change. compared with usual spin crossover transition. Thus, the charge-transfer phase transition around 120 K for (n-C3H7)(4)N[Fe-II Fe-III(dto)(3)] is regarded as spin entropy driven phase transition. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ssc.2004.02.034

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The title compound, [PtCl2(C2H8N2)(4)](HSO4)(4) or [Pt(C2H8N2)(2)][Pt2Cl2(C2H8N2)(2)](HSO4)(4), has a linear chain structure composed of square-planar [Pt(en)(2)](2+) and elongated octahedral trans-[PtCl2(en)(2)](2+) cations (en is ethylenediamine) stacked alternately, bridged by the Cl atoms, along the c axis. The Cl atom bridging the adjacent Pt atoms is disordered over two sites along the...Cl-Pt-IV-Cl...Pt-II...chain, which lies on a twofold axis. The Pt-IV-Cl and Pt-II...Cl bond lengths are 2.323 (2) and 3.142 (2) Angstrom, respectively. A structural parameter delta=(Pt-IV-Cl)/(Pt-II...Cl), indicating the mixed-valence state of the Pt atom (delta=0.739), shows a good correlation with the data of the intervalence charge-transfer (IVCT) absorption band.

DOI： 10.1107/S1600536802022584

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Bis[2-(aminomethyl)pyridine]platinum(II) chloride monohydrate [Pt(amp)(2)]Cl-2.H2O has been found to exhibit photochromism in single-crystalline phase. Single crystals of the chloride were changed from almost colorless to pale-blue by the irradiation of the light. Its aqueous solution, however, shows no photochromic behavior. Absorption bands induced by the irradiation of the light show dichroism in the single crystals. The photochromic behavior of the present platinum complex chloride is very interesting, because it occurs in single-crystalline phase but not in solution.

DOI： 10.1246/cl.2002.930

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

A new salt of BEDT-TTF with photo-sensitive transition metal complex [RuCl5(No)](2-) has been synthesized. The crystal structure was determined and attributed to the kappa-type salt. Although calculated band structure shows two dimensional Fermi surfaces and predicts a metallic behavior, the resistivity shows semiconducting temperature dependence up to 6 kbar. Both the ESR signals of BEDT-TTF+ and NO. exhibited a photo-induced effect.

DOI： 10.1080/10587250210746

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We have investigated optical property and crystal structure of a one-dimensional halogen-bridged platinum complex (MX chain compound) with a counter ion having two alkyl chains, [Pt(en)(2)][PtCl2(en)(2)]{(CH3(CH2)(7)CO2)(2)CH2CHSO3}(4).2H(2)O, to elucidate influence of molecular fastener effect of the long alkyl chain on mixed-valence state of the platinum atoms. Thermal-behavior observations of the complex were also performed using a polarizing optical microscope without and with crossed nicols to examine thermal change of the mixed-valence state and appearance of the liquid crystal phase. Consequently, the complex has exhibited that the interaction between the platinum atoms is strengthened and the Pt-II-Pt-IV distance is shortened by doubling the number of alkyl chains around the platinum complex moieties compared with a corresponding PtCl chain complex with a single alkyl chain counter ion. We have also observed a texture of liquid crystal at about 200 degreesC.

DOI： 10.1080/10587250290090633

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Ultrafast relaxation processes of photoexcited states of a quasi-one-dimensional halogen-bridged mixed-valence metal complex [Pt(en)(2)][Pt(en)(2)Cl-2](PF6)(4) have been investigated by femtosecond transient absorption spectra measurements. It has been found that a considerable part of the neutral soliton pairs is generated directly from photogenerated charge transfer excitons. Charged soliton pairs have been found to be generated from free electron-hole pairs. The rise time and the decay time of the charged soliton absorption band are 2.2 and 6.5 ps, respectively. The polaron pairs are generated from free electron-hole pairs within time resolution. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0022-2313(01)00369-6

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Femtosecond transient absorption spectra of a quasi-one-dimensional halogen-bridged mixed-valence metal complex [Pt(en)(2)]Pt(en)(2)Cl-2] (PF6)(4) have been measured. It has been found that the neutral solitons are generated from charge transfer excitons within the time resoution (300fsec). It is found that charged solitons are generated by the interband excitation. The rise time and decay time of the charged soliton absorption band are 2.2psec and 6.5psec respectively.

DOI： 10.1016/S0379-6779(00)01237-6

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Millisecond transient luminescence and absorption spectra of wide gap MX-chain compound, [Pd(en)(2)][Pt(en)(2)Br-2](ClO4)(4), have been measured. A delayed luminescence band has been found at 1.55 eV. The time evolution of the intensity of the luminescence is proportional to the first derivative of the intensity of the photoinduced polaron absorption. The delayed luminescence band is considered to be caused by the radiative recombination of the self-trapped excitons which are generated in the annihilation processes of the polarons. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0379-6779(00)00445-8

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M-2[(AuX2)-X-I][(AuX4)-X-111] (M = K, Rb, Cs; X = Cl, Br, I) are perovskite-type gold mixed-valence complexes, In this review, we describe their structural P-T phase diagram, the pressure induced Au valence transition from the Au-I,Au- III state to the Au-II one, which is coupled with a structural phase transition. The metallic cubic phase appearing under high pressure and high temperature can be obtained as a metastable phase even at ambient pressure and room temperature. In the pressure region below the Au valence transition, Cs-2[(AuX2)-X-1][(AuX4)-X-III] (X = Cl, Br, I) show metallic behavior, which is attributed to the Au valence-fluctuation. (C) 2000 Elsevier Science S.A. All rights reserved.

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X-ray scattering experiments have been performed on a quasi-one dimensional system, Ni1-xPdx(chxn)(2)Br-3, Strong diffuse scattering was observed for x > 0.7; and it was interpreted as due to spatial inhomogeneity in the valence of metal ions. This inhomogeneity takes the form of CDW in which the metal ions within a chain have valences alternating between +2 and +4. Correlations in the valence sequence could he determined parallel as well as perpendicular to the chain direction. Pair correlation functions deduced from the measurements show the existence Of strong correlation between the positions of bridging Br ions and those of Br counter ions. It is concluded that the valence of metal ions for z < 0.7 is +3. T2lese results are consistent with previous data on optical and magnetic measurements.

DOI： 10.1143/JPSJ.68.3948

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We have investigated the photo-induced and doping effects on the non-linear excitations (i.e. solitons and polarons) for the neutral MX chain system, [PtX2(en)][PtX4(en)](X=Cl, Br, I). From the analysis of the hyperfine structure of ESR signal in X=Cl salt, the photo-induced non-linear excitation is attributed to the neutral soliton. The iodine-doped X=Cl salt reveals a strong and broad ESR signal, whose intensity and g-value as a function of temperature suggest the existence of the dense non-linear excitations and the strong magnetic interaction between them.

DOI： 10.1016/S0379-6779(98)00667-5

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We have investigated organic/inorganic hybrids of MX chain in order to make a dynamical mixed-valence system as the first attempt. We have obtained the hybrids of the MX (PtCl, PtBr, PB) chains with organic sulfonate as a counter ion. They show deep red color for PtCl, greenish golden color for PtBr, cooper color for Ptl, strong dichroism and thin plate form. We've performed the X-ray crystal analysis of a Ptl chain of them, its having octanesulfonate ion as a counter ion. The result shows that the compound has a layered structure consisting of organic layers of long all;yl chains of the counter ion and inorganic layeres which include the one-dimensional structure, Pt-l.

DOI： 10.1016/S0379-6779(98)01161-8

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Language：Japanese   Publisher：The Japan Society of High Pressure Science and Technology  

In this report, a technique of single-crystal X-ray diffraction measurements under high pressures, using a diamond-anvil-cell with helium gas as an inert and hydrostatic pressure-transmitting medium, is introduced. The technique has been applied to three-dimensional halogen-bridged mixed-valence gold complexes, Cs<SUB>2</SUB>Au<SUP>I</SUP>Au<SUP>III</SUP>X<SUB>6</SUB> (X=Cl, I) to investigate the mixed-valence state and the crystal structure under high pressures up to 18 GPa and 7. 5 GPa, respectively. The pressure dependences of the unit cell parameters indicate that structural phase transitions occur from tetragonal to cubic at 12. 5 GPa for the Cl-bridged complex, and from tetragonal to monoclinic at 6. 0 GPa for the I-bridged complex. The Cl-bridged complex in the higher pressure phase has a space group, Pm3m and the cubic Perovskite-type structure.

DOI： 10.4131/jshpreview.8.280

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We have performed the single crystal X-ray structure analysis of the three-dimensional halogen-bridged mixed-valence compound, Cs2AuIAuIIICl6 under high pressures up to 18 GPa. The high pressure apparatus used is a diamond-anvil-cell with helium gas as an inert and hydrostatic pressure-transmitting medium. The pressure dependence of the unit cell parameters indicates a structural phase transition from tetragonal to cubic at 12.5 GPa. The high pressure phase has a space group, Pm3m. [mixed-valence, Au complex, perovskite structure, structural phase transition, high pressure]. © 1998, The Japan Society of High Pressure Science and Technology. All rights reserved.

DOI： 10.4131/jshpreview.7.329

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X-ray diffraction and optical absorption measurements were carried out on single crystals of [Pt(en)(2)][Pt(en)(2)Cl-2] (BF4)(4) (en = etylenediamine). This compound has a quasi-one dimensional structure with alternating (II and IV) Pt valences along the c-axis. An orthorhombic to monoclinic structural phase transition occurs around 255 K and the charge-transfer absorption edge was found to have a sudden shift at the transition. X-ray diffuse scattering was observed around (0 0 2n + 1) reciprocal points. While optical spectra were affected by irradiating the sample with blue light, the X-ray diffraction intensity did not change either by irradiation or by varying the sample temperature. We attribute the diffuse scattering to solitons produced during crystal growth. From measurements of thermal diffuse scattering, limited information about the phonon dispersion relation was obtained.

DOI： 10.1143/JPSJ.67.186

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Variation of crystal structure of LaCrO3 on pressure was investigated by X-ray diffraction for synchrotron radiation. X-ray diffraction pattern of LaCrO3 at room temperature under atmospheric pressure could be indexed assuming orthorhombic crystal symmetry. With the increase of pressure up to 5.4 GPa, structural phase transition was observed and crystal symmetry of LaCrO3 changed to hexagonal. The first order structural phase transition from orthorhombic to hexagonal is also observed under atmospheric pressure at 236 degrees C and variations of enthalpy, Delta H and molar volume, Delta V, at the phase transition were measured using differential scanning calorimetry and high temperature X-ray diffraction, respectively. By using Delta H, Delta V and Clapeyron formula, it was expected that the crystal phase transition occurred at room temperature under a pressure as low as 0.53 GPa. Presence of hexagonal phase in LaCrO3 under a pressure of 1.1-5.1 GPa showed agreement with the above thermodynamic expectation. (C) 1998 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0038-1098(98)00446-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMERICAN PHYSICAL SOC  

The time evolution of the thermal bleaching of the long-lived, photogenerated midgap absorption band in a PtCl chain compound is examined in a temperature range 220-330 K. The long-lived absorption arises from kinks each confined in a segment of the PtCl chain by energy barriers of the order of 0.5 eV. Because of a random distribution of the barrier height the pair coalescence decay shows a ln t dependence at all temperatures in the experimental range, 0-60 min, of time t after discontinuation of laser pumping.

DOI： 10.1103/PhysRevLett.79.2510

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The title compound, dicaesium gold(I) gold(III) hexaiodide, has a distorted perovskite structure. The crystal contains compressed and elongated [AuI6] octahedra stacked alternately along the [001] and [110] directions by sharing all the corner I atoms. The compound is also characterized by the assembly of the gold complex ions [(AuI2)-I-1](-) and [(AuI4)-I-III](-). The position of the two halogen atoms in (Cs2AuAuI6)-Au-I-I-III is closer to the midpoint between the two Au atoms than in (Cs2AuAuCl6)-Au-I-Cl-III. On the other hand, the distortion from the cubic system to the tetragonal system in the iodide is slightly larger than that in the chloride.

DOI： 10.1107/S0108270197000279

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We have investigated mid-gap absorption bands, their photo-induced absorption effect at various temperatures between liquid helium temperature and room temperature, and crystal structures between 150 K and 300 K in a neutral MX chain system, [PtX(2)(en)][PtX(4)(en)] (X=Cl, Br, I), which have one-dimensional structure, ...Pt-II...X-Pt-IV-X.... Temperature dependence of the intensity of the mid-gap absorption bands and the growth of the photo-induced absorption in [PtCl2(en)][PtCl4(en)] show that the generation efficiency of the mismatch of valence-alternation Is changed at 200-220 K. Temperature dependence of lattice parameters of [PtCl2(en)][PtCl4(en)] shows that the structural phase transition occurs at 220 K from the orthorhombic system to the monoclinic system by cooling. Comparison of the crystal structure between 195 K and 296 K shows that the basic structure does not change at the phase transition. The conformation of the chelate ring of the ethylenediamine is changed from the disordered state to the ordered state at the transition point by cooling. This result suggests that the order-disorder transition of the conformation of the ethylenediamine would be responsible for the generation efficiency of the mismatch of the valence alternation.

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The excitation energy dependence and time evolution of the photo-induced absorption (PA) spectra of [Pt(en)(2)][Pt(en)(2)Br-2](SO4)(2) . 6H(2)O have been investigated. Strong dependence of the PA-spectra on excitation photon energy has been found. This is explained by the photon-energy-dependent generation of polarons, neutral solitons, and a state (DG-state) which causes a pair of PA-bands. It is found that neutral solitons are efficiently generated from charge transfer excitons. On the other hand, polarons and DG-states are generated only from higher-energy excited states. It is also found that self-trapped excitons are most efficiently generated from the CT-excitons in the tail of the charge transfer exciton absorption band.

DOI： 10.1016/0022-2313(95)00121-2

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Optical absorption and Raman scattering in the title substance are studied. An intragap absorption band at 1.67 eV is enhanced efficiently by the irradiation with 488.0 nm light even at room temperature. Under hydrostatic pressures, although a phase transition occurs at 0.6 GPa, this band follows the midpoint of the charge-transfer gap well. The Raman scattering by the Pt-Cl stretching mode shows that the original CDW phase coexists with the high-pressure CDW phase under pressures up to 3.0 GPa.

DOI： 10.1016/0379-6779(94)03108-I

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We have investigated the size effect of the counter anion influencing to the mixed-valence state in MX chain platinum complexes. In order to study the counter-ion radius dependence of the mixed-valence state, we have measured the polarized reflectance spectra of [Pt(en)(2)][PtCl2(en)(2)]Y-4 (en=ethylenediamine, Y=PF6, HSO4, BF4) in single crystals, and analyzed the crystal structure of [Pt(en&gt;(2)][PtCl2(en)(2)](BF4)(4) by X-ray diffraction method. From comparing the tetrafluoroborate, the perchlorate, the hydrogensulfate and the hexafluorophosphate in the series of the chloro- bridged complex, we found that the mixed-valence gap of platinum decreases with decreasing the counter-anion radius.

DOI： 10.1016/0379-6779(94)03113-K

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The adsorption of tris(5,5'-dimethyl-2,2'-bipyridyl)ruthenium(II) ([Ru(dmbpy)(3)](2+))) by a colloidally dispersed montmorillonite or saponite is studied by electric dichroism measurements. [Ru(dmbpy)(3)](2+) is adsorbed up to 100% of the cation-exchange capacity (CEC). An angle (theta) between the threefold symmetry (C-3) axis of a bound chelate and the direction normal to a clay surface is determined from the reduced linear dichroism extrapolated to the infinite field strength. At the loading level less than 13% of CEC, theta is determined to be 54-53 degrees and 57-62 degrees for montmorillonite and saponite, respectively. The results are contrasted with the bindings of [Ru(phen)(3)](2+) (phen = 1,10-phenanthroline) and [Ru(bpy)(3)](2+) (bpy = 2,2'-bipyridyl). These molecules orient the C-3 axes roughly in the perpendicular direction on a clay surface (theta = 16-18 degrees). When the amount of [Ru(dmbpy)(3)](2+) adsorbed is increased to 83%, and 77% of CEC for montmorillonite and saponite, theta decreases to 43-46 degrees and 50-53 degrees, respectively. The changes are ascribed to the intermolecular interactions among the bound molecules. Notably, a definite difference is observed in the dichroism spectra whether the metal complex is adsorbed as a pure enantiomer or a racemic mixture at the higher loading level. These results are compared with the theoretical predictions based on the Monte Carlo simulations.

DOI： 10.1021/j100082a028

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We have measured the absorption and resonance Raman spectra in single crystals of the MX chain complex [Pt(en)(2)][PtBr2(en)(2)](SO4)(2) . 6H(2)O in order to study the mixed-valence state, the midgap state and the phase transition under various hydrostatic pressures up to 3.7 GPa at room temperature. Red shifts of both the intervalence charge-transfer absorption edge and the Pt-Br stretching mode Raman peak with increasing pressure show that the electronic state of Pt-II and Pt-IV in the mixed-valence state approaches that of Pt-III. An absorption band appearing above 2.5 GPa and a Raman peak appearing above 1.6 GPa suggest that a new phase coexists at pressures above 1.6 or 2.5 GPa. On the other hand, no enhancement of the optical absorption in the region of the midgap absorption bands (A-, B- and C-bands) is observed. This result shows that the midgap state is not generated by applying pressure at room temperature.

DOI： 10.1080/10587259408039339

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Photo-induced absorption (PA) spectra of [Pt(en)(2)][Pt(en)(2)X(2)] (SO2)(2).6H(2)O (X=Cl and Br) have been measured. Large excitation photon energy dependent changes were found in the features of the PA spectra. The excitation photon energy dependences are considered to be due to the difference between the relaxation processes of the charge transfer excitons and those of the higher energy excited states. Several new PA bands have been found.

DOI： 10.1080/10587259408039343

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA LAUSANNE  

Photo-generation and annihilation processes of the mid-gap states in quasi-one-dimensional halogen-bridged mixed-valence metal complexes (HMMC's) have been investigated by the excitation spectra measurements of photo-induced absorption (PA) bands and excitation power density dependence measurements of the PA bands. One kind of PA bands are efficiently generated from the CT-excitons. On the other hand, another kind of PA bands are efficiently generated from higher energy excited states. The generation efficiencies of the PA bands are proportional to the square root of the excitation light power density. This indicates that the mid-gap states which cause PA bands are mobile and are annihilated by the collision among them.

DOI： 10.1016/0379-6779(93)90134-I

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The mixed-valence states of halogen-bridged one dimensional platinum complexes have been investigated by the substitution of counter ions. The crystal structures of [Pt(en)2][PtCl2(en)2](PF6)4 (Cl-PF6), [Pt(en)2][PtCl2(en)2](HSO4)4 (Cl-HSO4) and [Pt(en)2][PtBr2(en)2](H2PO4)4.6H2O (Br-H2PO4) (en=ethylenediamine) have been determined by single-crystal X-ray diffraction, and their absorption edges have been measured at room temperature. The crystal data are: for Cl-PF6, monoclinic, P2/m, a=9.204(3), b=5.506(2), c=8.185(2)angstrom, 8=107.29(2)-degrees and Z=-1/2; for Cl-HSO4, orthorhombic, Ibam, a=9.261(l), b=14.422(2), c=10.929(1)angstrom, and Z=2; for Br-H2PO4, monoclinic, P2/a, a=19.463(2), b=5.722(l), c=8.325(1)angstrom, beta=101.59(l)-degrees and Z=1. The absorption edegs of the intervalence charge-transfer bands are c.a. 17,500cm-1 for Cl-PF6, c.a. 16,500cm-1 for Cl-HSO4 and c.a. 14,800cm-1 for Br-H2PO4. These results show that the counter ion size and the hydrogen atom of the counter ion influence the mixed-valence state. A mid-gap absorption band below the absorption edge is found at c.a. 14,700cm-1 in Cl-HSO4.

DOI： 10.1016/0379-6779(93)90135-J

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MUNKSGAARD INT PUBL LTD  

[Pt(II)(C2H8N2)2][PtIVBr2(C2H8N2)2](HSO4)4, M(r) = 1178.65, orthorhombic, Ibam, a = 9.263 (2), b = 14.317 (3), c = 11.036 (5) angstrom, V = 1463.6 (8) angstrom3, Z = 2, D(x) = 2.67 Mg M-3, lambda(Mo Kalpha) = 0.71069 angstrom, mu = 12.64 mm-1, F(000) = 1116, T = 296K, R = 0.049, wR = 0.079 for 773 observed reflections [\F(o)\ &gt; 3sigma(\F(o)\)]. The crystal contains columns composed of square-planar [Pt(en)2]2+ and elongated octahedral trans-[PtBr2(en)2]2+ units (en = ethylenediamine) stacked alternately along the c axis. The Br ions bridging the adjacent Pt ions are disordered over two sites along the ... Br-Pt(IV)-Br...Pt(II)... linear chain. The Pt(IV)-Br and Pt(II)...Br bonds are 2.474 (3) and 3.044 (4) angstrom, respectively. The structural parameter delta = (Pt(IV)-Br)/(Pt(II)...Br) bears a good correlation with the data of the intervalence charge-transfer (IVCT) absorption edge (delta = 0.813). The hydrogen bonds along the column [N...0 = 3.06 (3) and 3.24 (2) angstrom] and the intercolumn hydrogen bonds [O...0 = 3.13 (3) angstrom] stabilize the structure.

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Sulfates in one-dimensional halogen-bridged mixed-valence platinum complexes were synthesized in order to elucidate contributions of hydrogen bonds between in-plane ligand amines and counter ions to the mixed-valence state. Their intervalence charge-transfer bands measured by using the single crystals and their structures determined by single crystal X-ray diffraction analyses show that the energy difference of dz2 orbitals between the PtII and the PtIV becomes larger with decreasing linkages between the Pt units by the hydrogen bonds, comparing with Perchlorates and hydrogensulfates. © 1992, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1080/10587259208028773

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Other Link： http://orcid.org/0000-0003-1022-430X

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

We have investigated several kinds of midgap absorption spectra due to the mismatch of valence alternation(nonlinear excitations such as solitons and polarons) in various kinds of halogen bridged mixed-valence Pt complexes, [Pt(en)2][PtX2(en)2](SO4)2-6H2O(X=C1, Br and I), [PtX2(en)][PtX4(en)](X=C1 and Br), and [Pt(NH3)4][PtCl2(NH3)4](HSO4)4. Also we investigated the relationship between the stability of the mismatch of valence alternation and the crystal structure. © 1992, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1080/10587259208028767

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Other Link： http://orcid.org/0000-0003-1022-430X

Language：English   Publishing type：Research paper (scientific journal)  

Excitation spectra of the self-trapped exciton luminescence bands and those of photo-induced absorption bands of halogen-bridged mixed-valence metal complexes have been measured. The excitation spectra of luminescence bands begin to decrease from energies smaller than the peak energies of the charge transfer exciton absorption bands. The excitation spectra of photo-induced absorption bands begin to rise from the same energies. These show the competition between the self-trapped excitons and the photo-induced defect states in their generation processes. © 1992, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1080/10587259208028769

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

A new non-stoichiometric mixed-valence compound CsAu0.6Br2.6 has been prepared, and its powder X-ray diffraction profile, ESR spectra, and electrical conductivity determined. From its empirical formula the average valence of Au is + 2.67. Powder diffraction data indicate that the compound has a cubic perovskite structure [cubic lattice, space group Pm3m, a = 5.462(2) Å]. This means that the AuBr6 octahedra are crystallographically equivalent. ESR measurements show the existence of a +II formal oxidation state for Au. The conductivity is four orders of magnitude higher than that of the AuI-AuIII mixed-valence compound Cs2Au2Br6.

DOI： 10.1039/DT9910003115

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Other Link： http://orcid.org/0000-0003-1022-430X

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/bcsj.62.3906

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/0038-1098(89)91009-0

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Other Link： http://orcid.org/0000-0003-1022-430X

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/bcsj.62.1785

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PHYSICAL SOCIETY JAPAN  

DOI： 10.1143/JPSJ.56.3808

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MUNKSGAARD INT PUBL LTD  

DOI： 10.1107/S010827018609649X

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

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Language：Japanese  

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

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Total pages：231, 6p   Language：Japanese

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Language：Japanese Book type：Textbook, survey, introduction

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Total pages：152p   Language：Japanese

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Language：Japanese Book type：Textbook, survey, introduction

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Total pages：xxii, 344p, 図版2p   Language：Japanese

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Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Venue：東京工業大学キャンパスイノベーションセンター  

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