2002 年度実績報告書

酸素ホールの物理と化学:高原子価鉄族酸化物における相転移とダイナミックスの研究

研究課題

研究課題/領域番号	12304018
研究機関	東京大学
研究代表者	藤森淳東京大学, 大学院・新領域創成科学研究科, 教授 (10209108)
研究分担者	瀬戸誠京都大学, 原子炉実験所, 助教授 (40243109) 那須三郎大阪大学, 大学院・基礎工学研究科, 教授 (00030057) 高野幹夫京都大学, 化学研究所, 教授 (70068138)
キーワード	Fe酸化物 / 電荷分離 / 単結晶薄膜 / 単結晶育成 / メスバウアー分光 / 超高圧 / 光電子分光 / 軌道秩序
研究概要	1 6GPaの高圧下で三斜晶ペロブスカイトBiNiO_3を合成、放射光粉末X線回折を用いた構造解析で、AサイトがBi^<3+>とBi^<5+>に不均化した特殊な構造を持つことを明らかにした。また、Biイオンを一部La^<3+>で置換すると、置換量に依存する温度で絶縁体-金属転移が起こることを見いだした、この際構造も単斜晶から斜方晶のGeFeO_3型に変化しており、Bi^<5+>からNi^<2+>への電荷移動の結果Niが3価に酸化されて金属化が起こると考えられる。 2 SrFe_<1-X>Co_XO_3の強磁性状態におけるスピンおよび軌道磁気モーメントの組成依存性を、軟X線吸収磁気円二色性の測定により調べた。 3 FeO_6八面体層が2重構造をなすペロブスカイト型鉄酸化物Sr_3Fe_2O_7はネール温度120Kの反共磁性体であるが、343K以下の温度で電荷不均一化反応を示すことが^<57>Feメスバウアー分光におけるアイソマー・シフトおよびスペクトル形状から明らかになった。外部磁場下での測定から4.5Kでのスピン構造はヘリカル・スピン構造であることも明らかとなった。 4 FeO_6八面体層が3重構造をなすペロブスカイト型鉄酸化物LaSr_3Fe_3O_<10>の電荷不均一化反応は磁気秩序と同時に起こり、その温度は150Kであることが明らかとなった。スピン構造はSr_<2/3>La_<1/3>FeO_3と同じcollinear構造である。 5 金属鉄高圧相であるイプシロン鉄の低温強磁場下メスバウアー分光測定を行い、パウリ常磁性体であると結論した。 6 ペロブスカイト鉄酸化物DyFeO_3の元素を選択した^<161>Dy、^<57>Fe放射光核共鳴非弾性散乱測定およびX線非弾性散乱のデータに対して、シェルモデルを用いる事により振動モードの同定を行った。

研究成果

(34件)

すべてその他

すべて文献書誌 (34件)

[文献書誌] T.Kawakami: "Pressure-induced Transition from Charge-disproportionated antiferromagnetic State to Charge-uniform Ferromagnetic State in Sr_<2/3>La_<1/3>FeO_3"Phys. Rev. Lett.. 88. 037602-1-037602-4 (2002)
[文献書誌] R.Callens: "Stroboscopic Detection of Nuclear Forward-scattered Synchrotron Radiaiton"Phys. Rev. B. 65. 180404-1-180404-4 (2002)
[文献書誌] J.Matsuno: "Different Routes to Charge Disproportionation in Perovskites-Type Fe Oxides"Phys. Rev. B. 66. 107-111 (2002)
[文献書誌] K.Kuzushita: "Charge Disproportionation and Magnetic Order of Fe in LaSr_3Fe_3O_<10>"Solid State Commun.. 123. 107-111 (2002)
[文献書誌] J.Matsuno: "Chemical Potential Shift in La_<1-X>Sr_XMnO_3 : Photoemission Test of the Phase Separation Scenario"Europhys. Lett. 59. 252-257 (2002)
[文献書誌] Y.Kohsaka: "Growth of Na-Doped Ca2CuO2Cl2 Single Crystals under High Pressures of Several Gpa"J. Am. Chem. Soc.. 124. 12275-12278 (2002)
[文献書誌] S.Ishiwata: "High Pressure synthesis, Crystal Structure and Physical Properties of a New Ni(II) Perovskite BiNiO3"J. Mater. Chem.. 12. 3733-3737 (2002)
[文献書誌] T.Kawakami: "High-Pressure Mossbauer Study of Perovskite Iron Oxides"J. Physics : Condensed Matter. 14. 10713-10718 (2002)
[文献書誌] T.Uchino: "A Novel Pressure-Induced Polymorphic Transition from Fumed Silica to Transparent Amorphous SiO_2 at Room Temperature"J. Phys.: Condens. Matter. 14. 11111-11114 (2002)
[文献書誌] S.Nasu: "Mossbauer Study of ε-Fe under an External Magnetic Field"J. Phys.: Condens. Matter. 14. 11167-11171 (2002)
[文献書誌] M.Azuma: "Single-Crystal Growth of Transition Metal Oxides at High Pressures of Several GPa"J. Phys.: Condens. Matter. 14. 11321-11324 (2002)
[文献書誌] K.Suzuya: "Nuclear Resonant Inelastic Scattering of Synchrotron Radiation by Icosahedral Quasicrystal i-Al_<62>Cu_<25.5>Fe_<12.5> and Tetragonal Crystal omega-Al_<70>Cu_<20>Fe_<10>"J. Non-Crys. Solids. 312-314. 508-512 (2002)
[文献書誌] K.Okazaki: "Crossover in the Nature of the Metallic Phases in the Perovskite-Type RNiO_3"Phys. Rev. B. 67. 073101-1-073101-4 (2003)
[文献書誌] D.Wang: "An Effective Preparation Route to A Giant Magnetoresistance Material : Hydrothermal Synthesis and Characterization of La_<0.5>Sr_<0.5>MnO_3"Chem. Lett.. 32. 74-75 (2003)
[文献書誌] T.Kawakami: "High-Pressure Mossbauer and X-Ray Powder Diffraction Studies of SrFeO_3"J. Phys. Soc. Jpn. 72. 33-36 (2003)
[文献書誌] M.Seto: "Nuclear Resonant Inelastic and Forward Scattering of Synchrotron Radiation by ^<40>K Hyperfine"Hyperfine Interactions. (印刷中).
[文献書誌] J.Okamoto: "Photoemission Study of the Electronic Structure and the Metal-Semiconductor Transition in the Pyrochlore-Type Tl_2Ru_2O_7"Phys. Rev. B. (印刷中).
[文献書誌] S.Okubo: "Millimeter and Submillimeter wave ESR Measurement of Spin Ladder System Sr(Cu1-xZnx)203"in Proceedings of EPR in the 21st Century, ed. A. Kawamori, J. Yamauchi and H. Ohta, Elsevier Science B. V. 747-750 (2002)
[文献書誌] R.Yu: "Hydrothermal Formation of Novel Cerium Materials with Open-Framework Architectures"in Proceedings of the International Symposium on Solid State Chemistry, Frontiers of Solid State Chemistry, ed. S.H.Geng and J.S.Chen, World Scientific. 257-264 (2002)
[文献書誌] K.Okazaki: "Temperature-Dependent Electronic Structure of Nd_<1-X>Sm_XNiO_3"J. Phys. Chem. Solids. 63. 975-978 (2002)
[文献書誌] T.Saito: "Monoclinic Distortion in the Insulating Phase of PrNiO_3"Physica C. (印刷中).
[文献書誌] S.Ishiwata: "Suppression of A Site Charge Disproportionation in Bi_<1-x>La_xNiO_3"Physica C. (印刷中).
[文献書誌] A.Masuno: "Transport and Magnetic Properties of the Micro-Fabricated Perovskite-Type Manganese Oxides"Physica C. (印刷中).
[文献書誌] N.Ichikawa: "Non-Linear Conduction in the Charge-Disproportionated Phase of La_<1/3>Sr_<2/3>FeO_3"Physica C. (印刷中).
[文献書誌] A.Fujimori: "Electronic States and Novel Properties of Functional Transition-Metal Oxides : Tendency towards Cherge-Density Modulation"Trans. Mater. Res. Soc. Japan. (印刷中).
[文献書誌] J.Okamoto: "Electronic Structure of the Pyrochlore-Type Ru Oxides through the Metal-Insulator Transition"Acta Polonica. (印刷中).
[文献書誌] 東正樹: "スピン梯子化合物およびその周辺物質"物性研究. 74. 343 (2003)
[文献書誌] T.Terashima: "Preparation and the Anisotropy of (100)-Oriented La_<2-x>Sr_xCuO_4 EpitaxialThin Films"FEMD Newsletter. 4. 13 (2002)
[文献書誌] A.Fujimori: "Core-Level Photoemission Measurements of the Chemical PotentiaShift as a Probe of Correlated Electron Systems"J. Electron Spectrosc. Relat. Phenom.. 124. 127-138 (2002)
[文献書誌] 高野幹夫: "ペロブスカイト型Fe^<4+>-酸化物薄膜単結晶 -真空チャンバー内で酸素欠損を消す-"セラミックス. 37. 463-466 (2002)
[文献書誌] 高野幹夫: "ナノケミストリー -ものづくりの立場から-"学術月報. 55. 783-786 (2002)
[文献書誌] 東正樹: "GPa領域での遷移金属酸化物単結晶育成"日本物理学会誌. 57. 492-499 (2002)
[文献書誌] 東正樹: "放射光X線回折を利用し高圧合成研究"固体物理. 38. 141-150 (2003)
[文献書誌] M.Seto: "The Studies on Nuclear Resonant Scattering of Synchrotron Radiation by ^<40>K"Structural Chemistry. (印刷中).

2002 年度 実績報告書

酸素ホールの物理と化学:高原子価鉄族酸化物における相転移とダイナミックスの研究

研究代表者

藤森 淳 東京大学, 大学院・新領域創成科学研究科, 教授 (10209108)

研究成果

[文献書誌] T.Kawakami: "Pressure-induced Transition from Charge-disproportionated antiferromagnetic State to Charge-uniform Ferromagnetic State in Sr_<2/3>La_<1/3>FeO_3"Phys. Rev. Lett.. 88. 037602-1-037602-4 (2002)

[文献書誌] R.Callens: "Stroboscopic Detection of Nuclear Forward-scattered Synchrotron Radiaiton"Phys. Rev. B. 65. 180404-1-180404-4 (2002)

[文献書誌] J.Matsuno: "Different Routes to Charge Disproportionation in Perovskites-Type Fe Oxides"Phys. Rev. B. 66. 107-111 (2002)

[文献書誌] K.Kuzushita: "Charge Disproportionation and Magnetic Order of Fe in LaSr_3Fe_3O_<10>"Solid State Commun.. 123. 107-111 (2002)

[文献書誌] J.Matsuno: "Chemical Potential Shift in La_<1-X>Sr_XMnO_3 : Photoemission Test of the Phase Separation Scenario"Europhys. Lett. 59. 252-257 (2002)

[文献書誌] Y.Kohsaka: "Growth of Na-Doped Ca2CuO2Cl2 Single Crystals under High Pressures of Several Gpa"J. Am. Chem. Soc.. 124. 12275-12278 (2002)

[文献書誌] S.Ishiwata: "High Pressure synthesis, Crystal Structure and Physical Properties of a New Ni(II) Perovskite BiNiO3"J. Mater. Chem.. 12. 3733-3737 (2002)

[文献書誌] T.Kawakami: "High-Pressure Mossbauer Study of Perovskite Iron Oxides"J. Physics : Condensed Matter. 14. 10713-10718 (2002)

[文献書誌] T.Uchino: "A Novel Pressure-Induced Polymorphic Transition from Fumed Silica to Transparent Amorphous SiO_2 at Room Temperature"J. Phys.: Condens. Matter. 14. 11111-11114 (2002)

[文献書誌] S.Nasu: "Mossbauer Study of ε-Fe under an External Magnetic Field"J. Phys.: Condens. Matter. 14. 11167-11171 (2002)

[文献書誌] M.Azuma: "Single-Crystal Growth of Transition Metal Oxides at High Pressures of Several GPa"J. Phys.: Condens. Matter. 14. 11321-11324 (2002)

[文献書誌] K.Suzuya: "Nuclear Resonant Inelastic Scattering of Synchrotron Radiation by Icosahedral Quasicrystal i-Al_<62>Cu_<25.5>Fe_<12.5> and Tetragonal Crystal omega-Al_<70>Cu_<20>Fe_<10>"J. Non-Crys. Solids. 312-314. 508-512 (2002)

[文献書誌] K.Okazaki: "Crossover in the Nature of the Metallic Phases in the Perovskite-Type RNiO_3"Phys. Rev. B. 67. 073101-1-073101-4 (2003)

[文献書誌] D.Wang: "An Effective Preparation Route to A Giant Magnetoresistance Material : Hydrothermal Synthesis and Characterization of La_<0.5>Sr_<0.5>MnO_3"Chem. Lett.. 32. 74-75 (2003)

[文献書誌] T.Kawakami: "High-Pressure Mossbauer and X-Ray Powder Diffraction Studies of SrFeO_3"J. Phys. Soc. Jpn. 72. 33-36 (2003)

[文献書誌] M.Seto: "Nuclear Resonant Inelastic and Forward Scattering of Synchrotron Radiation by ^<40>K Hyperfine"Hyperfine Interactions. (印刷中).

[文献書誌] J.Okamoto: "Photoemission Study of the Electronic Structure and the Metal-Semiconductor Transition in the Pyrochlore-Type Tl_2Ru_2O_7"Phys. Rev. B. (印刷中).

[文献書誌] S.Okubo: "Millimeter and Submillimeter wave ESR Measurement of Spin Ladder System Sr(Cu1-xZnx)203"in Proceedings of EPR in the 21st Century, ed. A. Kawamori, J. Yamauchi and H. Ohta, Elsevier Science B. V. 747-750 (2002)

[文献書誌] R.Yu: "Hydrothermal Formation of Novel Cerium Materials with Open-Framework Architectures"in Proceedings of the International Symposium on Solid State Chemistry, Frontiers of Solid State Chemistry, ed. S.H.Geng and J.S.Chen, World Scientific. 257-264 (2002)

[文献書誌] K.Okazaki: "Temperature-Dependent Electronic Structure of Nd_<1-X>Sm_XNiO_3"J. Phys. Chem. Solids. 63. 975-978 (2002)

[文献書誌] T.Saito: "Monoclinic Distortion in the Insulating Phase of PrNiO_3"Physica C. (印刷中).

[文献書誌] S.Ishiwata: "Suppression of A Site Charge Disproportionation in Bi_<1-x>La_xNiO_3"Physica C. (印刷中).

[文献書誌] A.Masuno: "Transport and Magnetic Properties of the Micro-Fabricated Perovskite-Type Manganese Oxides"Physica C. (印刷中).

[文献書誌] N.Ichikawa: "Non-Linear Conduction in the Charge-Disproportionated Phase of La_<1/3>Sr_<2/3>FeO_3"Physica C. (印刷中).

[文献書誌] A.Fujimori: "Electronic States and Novel Properties of Functional Transition-Metal Oxides : Tendency towards Cherge-Density Modulation"Trans. Mater. Res. Soc. Japan. (印刷中).

[文献書誌] J.Okamoto: "Electronic Structure of the Pyrochlore-Type Ru Oxides through the Metal-Insulator Transition"Acta Polonica. (印刷中).

[文献書誌] 東正樹: "スピン梯子化合物およびその周辺物質"物性研究. 74. 343 (2003)

[文献書誌] T.Terashima: "Preparation and the Anisotropy of (100)-Oriented La_<2-x>Sr_xCuO_4 EpitaxialThin Films"FEMD Newsletter. 4. 13 (2002)

[文献書誌] A.Fujimori: "Core-Level Photoemission Measurements of the Chemical PotentiaShift as a Probe of Correlated Electron Systems"J. Electron Spectrosc. Relat. Phenom.. 124. 127-138 (2002)

[文献書誌] 高野幹夫: "ペロブスカイト型Fe^<4+>-酸化物薄膜単結晶 -真空チャンバー内で酸素欠損を消す-"セラミックス. 37. 463-466 (2002)

[文献書誌] 高野幹夫: "ナノケミストリー -ものづくりの立場から-"学術月報. 55. 783-786 (2002)

[文献書誌] 東正樹: "GPa領域での遷移金属酸化物単結晶育成"日本物理学会誌. 57. 492-499 (2002)

[文献書誌] 東正樹: "放射光X線回折を利用し高圧合成研究"固体物理. 38. 141-150 (2003)

[文献書誌] M.Seto: "The Studies on Nuclear Resonant Scattering of Synchrotron Radiation by ^<40>K"Structural Chemistry. (印刷中).

2002 年度実績報告書

藤森淳東京大学, 大学院・新領域創成科学研究科, 教授 (10209108)