• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1999 Fiscal Year Final Research Report Summary

Thoretical Study on Electronic Structures and Pressure-Induced Composite Phase Transitions of Solid Oxygen

Research Project

Project/Area Number 09640433
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field 固体物性Ⅱ(磁性・金属・低温)
Research InstitutionOsaka University

Principal Investigator

SUZUKI Naoshi  Sch. Engi. Sci., Osaka Univ., Professor, 基礎工学研究科, 教授 (40029559)

Co-Investigator(Kenkyū-buntansha) MIYAGI Hiroshi  Sch. Engi. Sci., Osaka Univ., Assoc. Professor, 基礎工学研究科, 助教授 (10029473)
Project Period (FY) 1997 – 1999
Keywordssolid oxygen / molecular phase / FP-LMTO method / electronic band structure / insulator-metal transition / band-overlapping / solid selenium / superconductivity
Research Abstract

From band structure calculations using full-potential (FP)-LMTO method for molecular phases of oxygen we have obtained the following important results:
1. At ambient pressure the most stable state is the AF state.
2. Pressure-induced insulator-metal transition occurs by band overlapping which closes the indirect energy gap. At the transition volume VィイD2MィエD2=25.98 ÅィイD13ィエD1, the magnetic moment still remains in each molecule.
3. With farther decreasing the volume the magnetic moment disappears and the paramagnetic metallic phase is realized at VィイD2MィエD2=11.36 ÅィイD13ィエD1 which corresponds to the ζ-phase at 116 GPa.
In order to see a possibility that the observed metallization is realized in a monatomic phase of solid oxygen we have performed band calculations of monatomic phases for the volume corresponding to that of the ζ-phase at 116 GPa(VィイD2MィエD2=11.36 ÅィイD13ィエD1). As the crystal structure we have chosen the β-Po type because it is the monatomic structure realized first under high p … More ressures in other VI-b elements. The β-Po type structure is rhombohedral and the sc, bcc and fcc structures are realized for special values of c/a of β-Po type structure. We have found that the total energy of β-Po oxygen is higher than that of the molecular ζ(monoclinic) phase obtained for the same volume. Therefore, judging from all the results of our calculations it is strongly suggested that a paramagnetic metallic state is realized in molecular solid oxygen under high pressures higher than about 100 GPa.
We investigated also pressure-induced superconductivity of β-Po Se (60 Gpa < P < 150 Gpa) and of bcc Se (150 Gpa < P) in the frame work of Allen-Dynes formalism. In the bcc phase the superconducting transition temperature TィイD2cィエD2 increases considerably with decreasing pressure, and TィイD2cィエD2 reaches more than 10 K at the transition from bcc to β-Po. The origin of this remarkable increase of TィイD2cィエD2 is mainly attributed to phonon anomaly in the middle of the ГN line. In β-Po phase, on the other hand, TィイD2cィエD2 is almost pressure independent (〜5K) and there is a large jump in TィイD2cィエD2 at the transition from β-Po to bcc. Less

  • Research Products

    (16 results)

All Other

All Publications (16 results)

  • [Publications] K. Yamaguchi: "First-Principles Calculations of Hyperfine Parameters of Solid Iodine under High Pressure"Rev. High Press. Sci. Tech.. 7. 157-159 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] M. Otani: "First-Principles Calculations of Electronic Band Structures of High Pressure Phases of Solid Oxygen"Rev. High Press. Sci. Tech.. 7. 178-180 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] N. Suzuki: "Electronic Structure, Electron-Lattice Interaction , and Lattice Dynamics in FCC Solid Bromine"Rev. High Press. Sci. Tech.. 7. 730-732 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] K. Yamaguchi: "Structural Properties of Molecular Solid Iodine under Pressure : First-Principles Study of Raman-active Ag modes and Hyperfine Parameters"Phys. Rev.. B57. 11141-11148 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] M. Otani: "Pressure-Induced Insulator-Metal Transition of Solid Oxygen - Band Structure Calculations"J. Phys. Condens. Matter. 10. 11603-11606 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] H. Miyagi: "First-Principles Study of Iodine and Bromine under High Pressure"J. Phys. Condens. Matter. 10. 11203-11213 (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] M. Otani: "Theoretical Study on Magnetic Properties of Low-Dimensional Oxygen Molecular Assemblies"Physica B. 265. 60-64 (1999)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] M. Otani: "Theoretical Study on Electronic Structure and Lattice Dynamics of Solid O and Se under High Pressures"Rev. High Press. Sci. Tech.. (in press).

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] K. Yamaguchi: "First-Principles Calculations of Hyperfine Parameters of Solid Iodine under High Pressure"Rev. High Press. Sci. Tech.. 7. 157-159 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] M. Otani: "First-Principles Calculations of Electronic Band Structures of High Pressure Phases of Solid Oxygen"Rev. High Press. Sci. Tech.. 7. 178-180 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] N. Suzuki: "Electronic Structure, Electron-Lattice Interaction, and Lattice Dynamics in FCC Solid Bromine"Rev. High Press. Sci. Tech.. 7. 730-732 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] K. Yamaguchi: "Structural Properties of Molecular Solid Iodine under Pressure : First-Principles Study of Raman-active Ag modes and Hyperfine Parameters"Phys. Rev.. B57. 11141-11148 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] M. Otani: "Pressure-Induced Insulator-Metal Transition of Solid Oxygen - Band Structure Calculations"J. Phys.: Condens. Matter. 10. 11603-11606 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] H. Miyagi: "First-Principles Study on Solid Iodine and Bromine under High Pressure"J. Phys.: Condens. Matter. 10. 11203-11213 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] M. Otani: "Theoretical Study on Magnetic Properties of Low-Dimensional Oxygen Molecular Assemblies"Physica B. 265. 60-64 (1999)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] M. Otani: "Theoretical Study on Electronic Structure and Lattice Dynamics of Solid O and Se under High Pressures"Rev. High Press. Sci. Tech.. (in press). (2000)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 2001-10-23  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi