2002 Fiscal Year Annual Research Report

分子性導体における電荷整列現象の研究

Research Project

Project/Area Number	13440214
Research Institution	Okazaki National Research Institutes
Principal Investigator	薬師久弥岡崎国立共同研究機構, 分子科学研究所, 教授 (20011695)
Co-Investigator(Kenkyū-buntansha)	山本薫岡崎国立共同研究機構, 分子科学研究所, 助手 (90321603)
Keywords	電荷整列 / 金属絶縁体転移 / 赤外ラマン分光 / 分子導体 / ウィグナー格子 / 局在化 / α-(BEDT-TTF)_2I_3 / (DI-DCNQI)_2Ag
Research Abstract	遍歴的な電荷が相転移に伴って局在化して電荷分布の濃淡を形成する現象(電荷整列)が一群の分子導体で発見され注目されている。この現象は遍歴性と局在性の境界領域にある分子導体に普遍的に存在する現象であるとの視点から系統的な研究を進めている。この研究では分子の持つ電荷に敏感な振動モードをプローブとして電子状態の変化を赤外・ラマン分光法によって研究している。本年度は4つの成果を挙げる事ができた。(1)実験手法の面では小型のサファイア・アンビルを用いて低温(>10K)・高圧力(<6GPa)の下でラマンスペクトルを測定する方法を開発した。圧力は電子状態に敏感な分子配列を連続的に変化させることができるので、P-T相図を調べる上で強力な手段となる。(2)θ-(BDT-TTP)_2Cu(NCS)_2の相転移前後のラマン線の形状から、低抵抗状態の電気伝導がホッピング機構によることを示唆した。また、100K付近から超格子が発生することと低温5K付近にスピン・パイエルス的な磁気相転移が存在することを発見した。(3)α-(BEDT-TTF)_2I_3の135Kにおける金属・絶縁体転移がバンド模型で記述できる遍歴的な電子状態から局在模型のウィグナー格子(電荷整列状態)への相転移であることをラマン分光法によって明らかにした。そして、ウィグナー格子上の電子密度とその配列様式を決定した。また、圧力をかけることによりこのウィグナー格子が融解して、バンド的な遍歴状態へ転移することを明らかにした。(4)^<13>C-NMRにより、(DI-DCNQI)_2Agは200K付近で電荷整列状態へ相転移すると提案されている。この物質の単結晶の赤外・ラマンスペクトルを低温・高圧下で側定し、室温で既に2量化の格子変形(4k_F変調)のゆらぎがあること、200K付近の電子状態の変化は4量化の格子変形(2k_F変調)が成長し始める事に対応していることを明らかにした。

Research Products

(32 results)

All Other

All Publications (32 results)

[Publications] K.Yamamoto, K.Yakushi, K.Miyagawa, K.Kanoda, A.Kawamoto: "Charge ordering in θ-(BEDT-TTF)_2RbZn(SCN)_4 studied by vibration spectroscopy"Phys. Rev. B. 65. 85110(8) (2002)
[Publications] J.Ouyang, K.Yakushi, T.Kinoshita, N.Nanbu, M.Aoyagi, Y.Misaki, K.Tanaka: "The assignment of the in-plane molecular vibrations of the BDT-TTP electron-donor molecule based on the polarized Raman and infrared spectra, where BDT-TTP is 2,5-bis(1,3-dithol-2-ylidene)-1,3,4,6-tetrathiapentalene"Spectrochim. Acta A. 58. 1643-1656 (2002)
[Publications] T.Nakamura, K.TAkahashi, T.Ise, T.Shirahata, M.Uruichi, K.Yakushi, T.Mori: "Magnetic Properties of Organic Spin-Ladder Systems, (BDTFP)_2X(PhCl)_<0.5>"Mol. Cryst. Liq. Cryst.. 376. 95-100 (2002)
[Publications] O.Drozdova, H.Yamochi, K.Yakushi, M.Uruichi, G.Saito: "Charge transfer degree of BO conmplexes"Mol. Cryst. Liq. Cryst.. 376. 135-140 (2002)
[Publications] Y.Yamashita, M.Tomura, M.Uruichi, K.Yakushi: "Synthesis and properties of π-extended TTF analogues and their cation radical and dication salts"Mol. Cryst. Liq. Cryst.. 376. 19-24 (2002)
[Publications] K.Yakushi, J.Ouyang, M.Shimonyan, Y.Misaki, K.Tanaka: "Charge order in θ-(BDT-TTP)_2Cu(NCS)_2"Mol. Cryst. Liq. Cryst.. 380. 53-59 (2002)
[Publications] Y.Ding, M.Simonyan, Y.Yonehara, M.Uruichi, K.Yakushi: "Formation of mixed crystal system Co_xNi_<1-x>Pc(AsF_6)_<0.5>"Mol. Cryst. Liq. Cryst.. 380. 283-287 (2002)
[Publications] K.Yamamoto, K.Yakushi, M.Inokchi, M.Kinoshita, G.Saito: "Charge disproportionation and its ordering pattern in θ and αtypes of BEDT-TTF salts studied by Raman and infrared spectroscopy"Mol. Cryst. Liq. Cryst.. 380. 221-226 (2002)
[Publications] M.Tokumoto, T.Mizutani, T.Kinoshita, J.S.Brooks, Y.Uwatoko, O.Drozdova, K.Yakushi, I.Tamura, H.Kobayashi, T.Mangetsu, J.Yamada, K.Ishida: "Effect of uniaxial pressure in organic superconductor κ-(BEDT-TTF)_2Cu(NCS)_2"Mol. Cryst. Liq. Cryst.. 380. (2002)
[Publications] G.Saito, H.Sasaki, T.Aoki, Y.Yohida, A.Otsuka, H.Yamochi, O.O.Drozdova, K.Yakushi, H.Kitagawa, T.Mitani: "Complex formation of ethylenedioxyethylenedithiotetrathiafulvalene(EDOEDT-TTF : EOET) and its self-assembling ability"J. Mater. Chem.. 12. 1640-1649 (2002)
[Publications] T.Yamamoto, H.Tajima, R.Kato, M.Uruichi, K.Yakushi: "Raman spectra of (Me_2-DCNQI)_2CuxLi_<1-x> (0<x<1). The evidence of charge separation at room temperature in a one-dimensional conductor having a quarter-filled band"J. Phvs. Soc. Jpn.. 71. 1956-1964 (2002)
[Publications] T.Nakamura, K.Takahashi, T.Shirahata, M.Uruichi, K.Yakushi, T, Mori: "Magnetic Investigation of Possible Quasi-One-dimensional Two-Leg Ladder Systems,(BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)"J. Phys. Soc. Jpn. 71. 2022-2030 (2002)
[Publications] M.Uruichi, K.Yakushi, T.Shlrahata, K.Takahashi, T.Mori, T.Nakamura: "Structural phase transition in quasi-1D conductors, (BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)[BDTFP=5,7-bis(1,3-dithiol-2-ylidene)-5,7-dihydrofhro[3,4-b]pyrazine]"J. Mater. Chem.. 12. 2696-2700 (2002)
[Publications] O.Drozdova, K.Yakushi, Y.misaki, K, Tanaka: "Optical study of two-dimensional organic metal (EO-TTP)_2AsF_6 (EO-TTP=2-(4,5-ethylenedioxy-1,3-dithiol-2-ylidene)-5-(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathis pentalene)"J. Solid State Chem.. 168. 497-502 (2002)
[Publications] M.Meneghetti, C.Pecile, K.Yakushi, K.Yamamoto, K.Kanoda, K.Hiraki: "Study of the phase transitions of (DI-DCNQI)_2M (M=Ag, Li, Cu) through the analysis of the temperature dependent vibronic and vibrational infrared absorptions"J. Solid State Chem.. 168. 632-638 (2002)
[Publications] K.Yakushi, K.Yamamoto, M.Simonyan, J.Ouyang, C.Nakano, Y.Misaki, K.Tanaka: "Charge-ordering and magnetic phase transitions in θ-(BDT-TTP)_2Cu(NCS)_2"Phys. Rev. B. 66. 235102(5) (2002)
[Publications] P.Toman, S.Nespurek, K.Yakushi: "Electronic states and infrared spectroscopy of nickel and cobalt phthalocyanines : Ab initio calculations for the neutral and cation state"J. Porphyrin and Phthalocyanine. (in press).
[Publications] K.Yakushi, K.Yamamoto, J.Ouyang, M.Smonyan, C.Nakano, Y.Misaki, K.Tanaka: "Charge ordering and phase transition in θ-(BDT-TTP)_2Cu(NCS)_2,"Synthetic Metals. (to be published).
[Publications] K.Yamamoto, K.Yakushi, K.Miyagawa, K.Kanoda, A.Kawamoto, J.Yamaura, T.Enoki: "Vibrational spectra of BEDT-TTF based 2D charge ordering systems"Synthetic Metals. (to be published).
[Publications] M.Uruichi, K.Yakushi, T.Shirahata, K.Takahashi, T.Mori, T.Nakamura: "Characterization of quasi-1D conductors, (BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)"Synthetic Metals. (to be published).
[Publications] O.Drozdova, K.Yakushi, A.Ota, H.Yamochi, G.Saito: "Spectroscopic study of the [0110] charge ordering (EDO-TTF)_2PF_6"Synthetic Metals. (to be published).
[Publications] O.Drozdova, K.Yakushi, H.Yamochi, G.Saito, D.B.Tanner: "Infrared study of the properties of the normal (metallic) phase of κ-(ET-^<13>C_4)_2Cu(CN)[N(CN)_2]"Synthetic Metals. (to be published).
[Publications] K.Takeda, I.Shirotani, K.Yakushi: "Insulator to metal transition and electronic spectra of bis(1,2-benzoquinonedioximato)-platinum(II), Pt(bqd)_2 at high pressure"Synthetic Metals. (to be published).
[Publications] K.Yakushi, R.Swietlik, K.Yamamoto, T.Kawamoto, T.Mori, Y.Misaki, K.Tanaka: "Charge disproportionation in the charge-transfer salts of TTP"Synth. Met.. (to be published).
[Publications] R.Wojciechowski, K.Yamamoto, K.Yakushi, A.Kawamoto: "Raman study of charge disproportionation in α-(BEDT0-TTF)_2I_3"Synth. Met.. (to be published).
[Publications] K.Suzuki, K.Yamamoto, K.Yakushi: "Charge ordering in θ-(BEDT-TTF)_2TIM(SCN)_4 (M=Co and Zn) studied by vibrational spectroscopy"Synth. Met.. (to be published).
[Publications] K.Yamamoto, K.Yakushi, K.Hiraki, T.Takahashi, K.Kanoda, M.Meneghetti, C.Pecile: "Charge distribution and molecular arrangement in (DI-DCNQI)_2Ag studied by high-pressure vibrational spectroscopy"Synth. Met.. (to be published).
[Publications] K.Yakushi, K.Yamamoto, R.Swietlik, R.Wojciechowshi, K.Suzuki, T.Kawamoto, T.Mori, Y.Misaki, K.Tanaka: "Spectroscopic studies of charge-ordering system in organic conductors"Macromolecular Symposia. (to be published).
[Publications] R.Swietlik, L Ouahab, J.Guillevic, K.Yakushi: "Infrared and Raman studies of the charge ordering in the organic semiconductor κ-[(Et)_4N](ET)_4Co(CN)_6・3H_2O"Macromolecular Symposia. (to be published).
[Publications] P.Toman, S.Nespurek, K.Yakushi: "Quantum chemical study of oxidation processes in metal-phthalocyanines"Macromolecular Symposia. (to be puvlished).
[Publications] R.Wojciechowski, K.Yamamoto, K.Yakushi, M.Inokuchi, A.Kawamoto: "High-pressure Raman study of the charge ordering in α-(BEDT-TTF)_2I_3"Phys. Rev. B. (to be publishied).
[Publications] R.Swietlik, A.Lapinski, L.Ouahab, K.Yakushi: "Charge ordering in the κ-phase BEDT-TTF salts with Co(CN)_6 and Fe(CN)_6 anions studied by infrared and Raman spectroscopy"Les Compte Rendus de l'Academie de Sciences(Pairs). (to be publishied).

2002 Fiscal Year Annual Research Report

分子性導体における電荷整列現象の研究

Principal Investigator

薬師 久弥 岡崎国立共同研究機構, 分子科学研究所, 教授 (20011695)

Research Products

[Publications] K.Yamamoto, K.Yakushi, K.Miyagawa, K.Kanoda, A.Kawamoto: "Charge ordering in θ-(BEDT-TTF)_2RbZn(SCN)_4 studied by vibration spectroscopy"Phys. Rev. B. 65. 85110(8) (2002)

[Publications] T.Nakamura, K.TAkahashi, T.Ise, T.Shirahata, M.Uruichi, K.Yakushi, T.Mori: "Magnetic Properties of Organic Spin-Ladder Systems, (BDTFP)_2X(PhCl)_<0.5>"Mol. Cryst. Liq. Cryst.. 376. 95-100 (2002)

[Publications] O.Drozdova, H.Yamochi, K.Yakushi, M.Uruichi, G.Saito: "Charge transfer degree of BO conmplexes"Mol. Cryst. Liq. Cryst.. 376. 135-140 (2002)

[Publications] Y.Yamashita, M.Tomura, M.Uruichi, K.Yakushi: "Synthesis and properties of π-extended TTF analogues and their cation radical and dication salts"Mol. Cryst. Liq. Cryst.. 376. 19-24 (2002)

[Publications] K.Yakushi, J.Ouyang, M.Shimonyan, Y.Misaki, K.Tanaka: "Charge order in θ-(BDT-TTP)_2Cu(NCS)_2"Mol. Cryst. Liq. Cryst.. 380. 53-59 (2002)

[Publications] Y.Ding, M.Simonyan, Y.Yonehara, M.Uruichi, K.Yakushi: "Formation of mixed crystal system Co_xNi_<1-x>Pc(AsF_6)_<0.5>"Mol. Cryst. Liq. Cryst.. 380. 283-287 (2002)

[Publications] K.Yamamoto, K.Yakushi, M.Inokchi, M.Kinoshita, G.Saito: "Charge disproportionation and its ordering pattern in θ and αtypes of BEDT-TTF salts studied by Raman and infrared spectroscopy"Mol. Cryst. Liq. Cryst.. 380. 221-226 (2002)

[Publications] M.Tokumoto, T.Mizutani, T.Kinoshita, J.S.Brooks, Y.Uwatoko, O.Drozdova, K.Yakushi, I.Tamura, H.Kobayashi, T.Mangetsu, J.Yamada, K.Ishida: "Effect of uniaxial pressure in organic superconductor κ-(BEDT-TTF)_2Cu(NCS)_2"Mol. Cryst. Liq. Cryst.. 380. (2002)

[Publications] G.Saito, H.Sasaki, T.Aoki, Y.Yohida, A.Otsuka, H.Yamochi, O.O.Drozdova, K.Yakushi, H.Kitagawa, T.Mitani: "Complex formation of ethylenedioxyethylenedithiotetrathiafulvalene(EDOEDT-TTF : EOET) and its self-assembling ability"J. Mater. Chem.. 12. 1640-1649 (2002)

[Publications] T.Yamamoto, H.Tajima, R.Kato, M.Uruichi, K.Yakushi: "Raman spectra of (Me_2-DCNQI)_2CuxLi_<1-x> (0<x<1). The evidence of charge separation at room temperature in a one-dimensional conductor having a quarter-filled band"J. Phvs. Soc. Jpn.. 71. 1956-1964 (2002)

[Publications] T.Nakamura, K.Takahashi, T.Shirahata, M.Uruichi, K.Yakushi, T, Mori: "Magnetic Investigation of Possible Quasi-One-dimensional Two-Leg Ladder Systems,(BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)"J. Phys. Soc. Jpn. 71. 2022-2030 (2002)

[Publications] M.Uruichi, K.Yakushi, T.Shlrahata, K.Takahashi, T.Mori, T.Nakamura: "Structural phase transition in quasi-1D conductors, (BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)[BDTFP=5,7-bis(1,3-dithiol-2-ylidene)-5,7-dihydrofhro[3,4-b]pyrazine]"J. Mater. Chem.. 12. 2696-2700 (2002)

[Publications] O.Drozdova, K.Yakushi, Y.misaki, K, Tanaka: "Optical study of two-dimensional organic metal (EO-TTP)_2AsF_6 (EO-TTP=2-(4,5-ethylenedioxy-1,3-dithiol-2-ylidene)-5-(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathis pentalene)"J. Solid State Chem.. 168. 497-502 (2002)

[Publications] M.Meneghetti, C.Pecile, K.Yakushi, K.Yamamoto, K.Kanoda, K.Hiraki: "Study of the phase transitions of (DI-DCNQI)_2M (M=Ag, Li, Cu) through the analysis of the temperature dependent vibronic and vibrational infrared absorptions"J. Solid State Chem.. 168. 632-638 (2002)

[Publications] K.Yakushi, K.Yamamoto, M.Simonyan, J.Ouyang, C.Nakano, Y.Misaki, K.Tanaka: "Charge-ordering and magnetic phase transitions in θ-(BDT-TTP)_2Cu(NCS)_2"Phys. Rev. B. 66. 235102(5) (2002)

[Publications] P.Toman, S.Nespurek, K.Yakushi: "Electronic states and infrared spectroscopy of nickel and cobalt phthalocyanines : Ab initio calculations for the neutral and cation state"J. Porphyrin and Phthalocyanine. (in press).

[Publications] K.Yakushi, K.Yamamoto, J.Ouyang, M.Smonyan, C.Nakano, Y.Misaki, K.Tanaka: "Charge ordering and phase transition in θ-(BDT-TTP)_2Cu(NCS)_2,"Synthetic Metals. (to be published).

[Publications] K.Yamamoto, K.Yakushi, K.Miyagawa, K.Kanoda, A.Kawamoto, J.Yamaura, T.Enoki: "Vibrational spectra of BEDT-TTF based 2D charge ordering systems"Synthetic Metals. (to be published).

[Publications] M.Uruichi, K.Yakushi, T.Shirahata, K.Takahashi, T.Mori, T.Nakamura: "Characterization of quasi-1D conductors, (BDTFP)_2X(PhCl)_<0.5> (X=PF_6,AsF_6)"Synthetic Metals. (to be published).

[Publications] O.Drozdova, K.Yakushi, A.Ota, H.Yamochi, G.Saito: "Spectroscopic study of the [0110] charge ordering (EDO-TTF)_2PF_6"Synthetic Metals. (to be published).

[Publications] O.Drozdova, K.Yakushi, H.Yamochi, G.Saito, D.B.Tanner: "Infrared study of the properties of the normal (metallic) phase of κ-(ET-^<13>C_4)_2Cu(CN)[N(CN)_2]"Synthetic Metals. (to be published).

[Publications] K.Takeda, I.Shirotani, K.Yakushi: "Insulator to metal transition and electronic spectra of bis(1,2-benzoquinonedioximato)-platinum(II), Pt(bqd)_2 at high pressure"Synthetic Metals. (to be published).

[Publications] K.Yakushi, R.Swietlik, K.Yamamoto, T.Kawamoto, T.Mori, Y.Misaki, K.Tanaka: "Charge disproportionation in the charge-transfer salts of TTP"Synth. Met.. (to be published).

[Publications] R.Wojciechowski, K.Yamamoto, K.Yakushi, A.Kawamoto: "Raman study of charge disproportionation in α-(BEDT0-TTF)_2I_3"Synth. Met.. (to be published).

[Publications] K.Suzuki, K.Yamamoto, K.Yakushi: "Charge ordering in θ-(BEDT-TTF)_2TIM(SCN)_4 (M=Co and Zn) studied by vibrational spectroscopy"Synth. Met.. (to be published).

[Publications] K.Yamamoto, K.Yakushi, K.Hiraki, T.Takahashi, K.Kanoda, M.Meneghetti, C.Pecile: "Charge distribution and molecular arrangement in (DI-DCNQI)_2Ag studied by high-pressure vibrational spectroscopy"Synth. Met.. (to be published).

[Publications] K.Yakushi, K.Yamamoto, R.Swietlik, R.Wojciechowshi, K.Suzuki, T.Kawamoto, T.Mori, Y.Misaki, K.Tanaka: "Spectroscopic studies of charge-ordering system in organic conductors"Macromolecular Symposia. (to be published).

[Publications] R.Swietlik, L Ouahab, J.Guillevic, K.Yakushi: "Infrared and Raman studies of the charge ordering in the organic semiconductor κ-[(Et)_4N](ET)_4Co(CN)_6・3H_2O"Macromolecular Symposia. (to be published).

[Publications] P.Toman, S.Nespurek, K.Yakushi: "Quantum chemical study of oxidation processes in metal-phthalocyanines"Macromolecular Symposia. (to be puvlished).

[Publications] R.Wojciechowski, K.Yamamoto, K.Yakushi, M.Inokuchi, A.Kawamoto: "High-pressure Raman study of the charge ordering in α-(BEDT-TTF)_2I_3"Phys. Rev. B. (to be publishied).

[Publications] R.Swietlik, A.Lapinski, L.Ouahab, K.Yakushi: "Charge ordering in the κ-phase BEDT-TTF salts with Co(CN)_6 and Fe(CN)_6 anions studied by infrared and Raman spectroscopy"Les Compte Rendus de l'Academie de Sciences(Pairs). (to be publishied).

薬師久弥岡崎国立共同研究機構, 分子科学研究所, 教授 (20011695)