1999 Fiscal Year Annual Research Report

放射光を用いた超臨界金属流体の静的・動的構造の解明

Research Project

Project/Area Number	11102004
Research Institution	Hiroshima University
Principal Investigator	田村剛三郎広島大学, 総合科学部, 教授 (30155262)
Co-Investigator(Kenkyū-buntansha)	内海渉日本原子力研究所, 関西研究所, 研究員星野公三広島大学, 総合科学部, 教授 (30134951) 乾雅祝広島大学, 総合科学部, 助教授 (40213136) 舟越賢一財団法人高輝度光科学研究センター, 利用促進部門, 研究員
Keywords	超臨界金属流体 / 放射光 / 金属-非金属転移 / 流体水銀 / 流体セレン / X線回折 / X線小角散乱 / X線非弾性散乱
Research Abstract	1、X線の回折測定 SPring-8の高温構造物性ビームラインBL04B1は、最大エネルギー約150KeVの白色X線の出てくるビームラインである。ここでは、2000気圧までのガス圧実験が可能である。我々は、数年前から超臨界金属流体の短・中距離構造を明らかにする目的で、このビームラインの立ち上げを行ってきた。流体水銀およびセレンを対象とし、液体状態から高密度気体までの広い密度範囲でエネルギー分散X線回折測定を行い、ミクロ構造について新しい知見を得ることができた。流体水銀に関する第一の成果は、水銀が膨張するときミクロにみてどのように膨張するかという問いに対する答えが得られたことで、水銀は結晶が熱膨張するときのように一様に膨張するのではなくランダムな配列をしている原子集団の中から原子を一つ一つ抜き出すようにして不均質な膨張をすることが明らかになった。さらに詳細にみると、三つの領域すなわち金属領域、金属-非金属転移領域、高密度気体領域で膨張の仕方が異なることが分かった。流体セレンについては、半導体-金属転移に際し二配位鎖構造が保持されかつ原子間距離はむしろ短くなることが判明した。 2、X線小角散乱測定上記ビームラインに隣接するBL04B2において、超臨界金属流体の密度のゆらぎについての情報を得るためX線小角散乱測定装置の立ち上げを行った。このためにダイアモンド高圧窓を有する内熱型の高圧容器(1700℃、2000気圧)を開発した。38KeVの単色X線を用いて流体セレンのX線小角散乱測定を行い、臨界密度近傍で散乱強度の増加を観測することができた。また、高圧窓からの散乱が大きいので材質を変える必要があること等、今後改善すべき点も明らかになった。これと平行して、広島大学においてもX線小角散乱実験を進めている。このために、強力X線発生装置とイメージングプレート検出器を購入した。

Research Products

(27 results)

All Other

All Publications (27 results)

[Publications] K.Tamura: "Energy-dispersive x-ray diffraction equipment for fluid at extreme condition of high temprenature and high pressures"Review of Scientific Instruments. 70巻. 144-152 (1999)
[Publications] Y.Sakaguchi: "Transient direct-current conductivity of lignid selenium : an indication of the photoinduced semiconductor-metal transition"Journal of Physics : Condensed Matter. 11巻. 659-670 (1999)
[Publications] K.Tamura: "In situ x-ray diffraction and XAFS studies of expanded fluid selenium"Materials Research Society Bulletin. 24巻. 26-31 (1999)
[Publications] C.Li: "Electronic structure study of liquid germanium based on x-ray-absorption near-edge structure spectroscopy"Physical Review B. 59巻. 1571-1574 (1999)
[Publications] K.Tamura: "X-ray diffraction studies of xpanded fluid mercury using synchrotron radiation at SPring-8"Japan Journal of Applied Physics. 38巻. 452-455 (1999)
[Publications] K.Tamura: "Structural studies of expanded fluid mercury using synchrotron radiation"Journal of Non-Crystalline Solids. 250-252巻. 148-153 (1999)
[Publications] M.Inui: "X-ray diffraction measurements for expanded fluid Se using synchrotron radiation"Journal of Non-Crystalline Solids. 250-252巻. 519-524 (1999)
[Publications] M.Inui: "X-ray absorption fine structure studies on expanded fluid Se : From liquid to dense vapour"Journal of Non-Crystalline Solids. 250-252巻. 525-530 (1999)
[Publications] Y.Sakaguchi: "A large photoinduced change in liquid selenium : transient dc conductivity and trancient absorption measurements"Journal of Non-Crystalline Solids. 250-252巻. 441-446 (1999)
[Publications] M.Inui: "Small angle x-ray scattering measurements for fluid Se near the critical point"Journal of Non-Crystalline Solids. 250-252巻. 531-536 (1999)
[Publications] Y.Kawakita: "Local structure of liquid and vitreous V_2O_5 and P_2O_5"Journal of Physics and Chemistry of Solids. 60巻. 1483-1486 (1999)
[Publications] 田村剛三郎: "Spring-8における超臨界金属流体の構造研究-膨張する水銀-"固体物理. 34巻. 199-207 (1999)
[Publications] 内海渉: "Spring-8高温構造物性ビームラインBL04B2"放射光. 12巻. 17-23 (1999)
[Publications] 田村剛三郎: "超臨界金属流体の構造研究-膨張する水銀-"Spring-8利用者情報. 4巻. 38-42 (1999)
[Publications] K.Hoshino: "Structure and electronic states of expanded and compressed liquid alkali metals by the ab initio molecular dynamics simulation"High Temperature Materials and Processes. 18巻. 79-85 (1999)
[Publications] F.Shimojo: "Atomic structure and charge transfer in liquid Rb-Te mixtures : ab initio molecular-dynamics simulation"Physical Review B. 59巻. 3514-3520 (1999)
[Publications] Y.Senda: "The origin of the first sharp diffraction peak in liquid Na-Pb alloys : ab initio molecular-dynamics simulation"Journal of Physics : Condensed Matter. 11巻. 2199-2210 (1999)
[Publications] F.Shimojo: "The microscopic mechanism of the semiconductor-metal transition in liquid arsenic triselenide"Journal of Physics : Condensed Matter. 11巻. L153-L158 (1999)
[Publications] F.Shimojo: "First-principles molecular-dynamics simulation of proton diffusion in perovskite oxides"Solid State Ionics. 113-115巻. 319-323 (1999)
[Publications] Y.Zempo: "Structural and electronic properties of liquid rubidium"Computational Materials Sciences. 14巻. 19-27 (1999)
[Publications] K.Hoshino: "The photo-induced structural change in a Se chain and a Se_8-ring : an ab initio molecular-dynamics simulation"Journal of Physical Society of Japan. 68巻. 1907-1911 (1999)
[Publications] Y.senda: "Composition dependence of the structure and the electronic states of liquid K-Pb alloy : ab initio molecular-dynamics simulation"Journal of Physics : Condensed Matter. 11巻. 5245-5256 (1999)
[Publications] Y.Senda: "Structure and electronic states of liquid Na-Pb alloys by an ab initio molecular-dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 258-262 (1999)
[Publications] S.Munejiri: "Density dependence of the velocity of sound in expanded liquid mercury by a large-scale molecular dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 144-147 (1999)
[Publications] F.Shimojo: "Effects of the spin polarization on structural and electronic properties of supercritical fluid selenium"Journal of Physics : Condensed Matter. 11巻. 8829-8838 (1999)
[Publications] F.Shimojo: "Structure and electronic properties of supercritical selenium : an ab initio molecular-dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 542-546 (1999)
[Publications] F.Shimojo: "Ab initio molecular-dynamics study of liquid alkal-tellurium mixtures"Journal of Non-Crystalline Solids. 250-252巻. 547-551 (1999)

1999 Fiscal Year Annual Research Report

放射光を用いた超臨界金属流体の静的・動的構造の解明

Principal Investigator

田村 剛三郎 広島大学, 総合科学部, 教授 (30155262)

Research Products

[Publications] K.Tamura: "Energy-dispersive x-ray diffraction equipment for fluid at extreme condition of high temprenature and high pressures"Review of Scientific Instruments. 70巻. 144-152 (1999)

[Publications] Y.Sakaguchi: "Transient direct-current conductivity of lignid selenium : an indication of the photoinduced semiconductor-metal transition"Journal of Physics : Condensed Matter. 11巻. 659-670 (1999)

[Publications] K.Tamura: "In situ x-ray diffraction and XAFS studies of expanded fluid selenium"Materials Research Society Bulletin. 24巻. 26-31 (1999)

[Publications] C.Li: "Electronic structure study of liquid germanium based on x-ray-absorption near-edge structure spectroscopy"Physical Review B. 59巻. 1571-1574 (1999)

[Publications] K.Tamura: "X-ray diffraction studies of xpanded fluid mercury using synchrotron radiation at SPring-8"Japan Journal of Applied Physics. 38巻. 452-455 (1999)

[Publications] K.Tamura: "Structural studies of expanded fluid mercury using synchrotron radiation"Journal of Non-Crystalline Solids. 250-252巻. 148-153 (1999)

[Publications] M.Inui: "X-ray diffraction measurements for expanded fluid Se using synchrotron radiation"Journal of Non-Crystalline Solids. 250-252巻. 519-524 (1999)

[Publications] M.Inui: "X-ray absorption fine structure studies on expanded fluid Se : From liquid to dense vapour"Journal of Non-Crystalline Solids. 250-252巻. 525-530 (1999)

[Publications] Y.Sakaguchi: "A large photoinduced change in liquid selenium : transient dc conductivity and trancient absorption measurements"Journal of Non-Crystalline Solids. 250-252巻. 441-446 (1999)

[Publications] M.Inui: "Small angle x-ray scattering measurements for fluid Se near the critical point"Journal of Non-Crystalline Solids. 250-252巻. 531-536 (1999)

[Publications] Y.Kawakita: "Local structure of liquid and vitreous V_2O_5 and P_2O_5"Journal of Physics and Chemistry of Solids. 60巻. 1483-1486 (1999)

[Publications] 田村剛三郎: "Spring-8における超臨界金属流体の構造研究-膨張する水銀-"固体物理. 34巻. 199-207 (1999)

[Publications] 内海渉: "Spring-8高温構造物性ビームラインBL04B2"放射光. 12巻. 17-23 (1999)

[Publications] 田村剛三郎: "超臨界金属流体の構造研究-膨張する水銀-"Spring-8利用者情報. 4巻. 38-42 (1999)

[Publications] K.Hoshino: "Structure and electronic states of expanded and compressed liquid alkali metals by the ab initio molecular dynamics simulation"High Temperature Materials and Processes. 18巻. 79-85 (1999)

[Publications] F.Shimojo: "Atomic structure and charge transfer in liquid Rb-Te mixtures : ab initio molecular-dynamics simulation"Physical Review B. 59巻. 3514-3520 (1999)

[Publications] Y.Senda: "The origin of the first sharp diffraction peak in liquid Na-Pb alloys : ab initio molecular-dynamics simulation"Journal of Physics : Condensed Matter. 11巻. 2199-2210 (1999)

[Publications] F.Shimojo: "The microscopic mechanism of the semiconductor-metal transition in liquid arsenic triselenide"Journal of Physics : Condensed Matter. 11巻. L153-L158 (1999)

[Publications] F.Shimojo: "First-principles molecular-dynamics simulation of proton diffusion in perovskite oxides"Solid State Ionics. 113-115巻. 319-323 (1999)

[Publications] Y.Zempo: "Structural and electronic properties of liquid rubidium"Computational Materials Sciences. 14巻. 19-27 (1999)

[Publications] K.Hoshino: "The photo-induced structural change in a Se chain and a Se_8-ring : an ab initio molecular-dynamics simulation"Journal of Physical Society of Japan. 68巻. 1907-1911 (1999)

[Publications] Y.senda: "Composition dependence of the structure and the electronic states of liquid K-Pb alloy : ab initio molecular-dynamics simulation"Journal of Physics : Condensed Matter. 11巻. 5245-5256 (1999)

[Publications] Y.Senda: "Structure and electronic states of liquid Na-Pb alloys by an ab initio molecular-dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 258-262 (1999)

[Publications] S.Munejiri: "Density dependence of the velocity of sound in expanded liquid mercury by a large-scale molecular dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 144-147 (1999)

[Publications] F.Shimojo: "Effects of the spin polarization on structural and electronic properties of supercritical fluid selenium"Journal of Physics : Condensed Matter. 11巻. 8829-8838 (1999)

[Publications] F.Shimojo: "Structure and electronic properties of supercritical selenium : an ab initio molecular-dynamics simulation"Journal of Non-Crystalline Solids. 250-252巻. 542-546 (1999)

[Publications] F.Shimojo: "Ab initio molecular-dynamics study of liquid alkal-tellurium mixtures"Journal of Non-Crystalline Solids. 250-252巻. 547-551 (1999)

田村剛三郎広島大学, 総合科学部, 教授 (30155262)