Anharmonic effective pair potentials in CaTiO3, SrTiO3 and CaGeO3 perovskite

Akira Yoshiasa; Kenji Nakajima; Kei Ichiro Murai; Maki Okube

doi:10.1107/S0909049500020689

Anharmonic effective pair potentials in CaTiO₃, SrTiO₃ and CaGeO₃ perovskite

Akira Yoshiasa, Kenji Nakajima, Kei Ichiro Murai, Maki Okube

Materials Development Division

Research output: Contribution to journal › Article › peer-review

13 Citations (Scopus)

Abstract

The temperature dependence of EXAFS Debye-Waller factors in CaTiO₃, SrTiO₃ and CaGeO₃ perovskite was investigated with the cumulant expansion method. The CaGeO₃ perovskite as an analogue of the Earth's lower-mantle mineral was synthesized in a cubic anvil type apparatus under 10 GPa 1250 K. The Ca, Ti and Ge K-edge EXAFS spectra were measured in transmission mode at temperature up to 1100 K. The effective pair potentials, V(u)= α u²/2+βu³/3!, were evaluated and the Grüneisen parameter were calculated. The potential coefficients α and β for Ti-O bond in CaTiO₃ are 6.9 eVÅ^-2 and -38 eVÅ^-3, respectively. Those for Ge-O bond in CaGeO₃ are 9.8 eVÅ^-2 and -36 eVÅ^-3, respectively.

Original language	English
Pages (from-to)	940-942
Number of pages	3
Journal	Journal of Synchrotron Radiation
Volume	8
Issue number	2
DOIs	https://doi.org/10.1107/S0909049500020689
Publication status	Published - 2001 Mar 1

Keywords

Anharmonic effective pair potential
EXAFS Debye-Waller factor
Metastable CaGeO
Perovskite
SrTiO

ASJC Scopus subject areas

Radiation
Nuclear and High Energy Physics
Instrumentation

Access to Document

10.1107/S0909049500020689

Cite this

@article{42d61c40ac0743e38ca4e2ddc8ed6f55,

title = "Anharmonic effective pair potentials in CaTiO3, SrTiO3 and CaGeO3 perovskite",

abstract = "The temperature dependence of EXAFS Debye-Waller factors in CaTiO3, SrTiO3 and CaGeO3 perovskite was investigated with the cumulant expansion method. The CaGeO3 perovskite as an analogue of the Earth's lower-mantle mineral was synthesized in a cubic anvil type apparatus under 10 GPa 1250 K. The Ca, Ti and Ge K-edge EXAFS spectra were measured in transmission mode at temperature up to 1100 K. The effective pair potentials, V(u)= α u2/2+βu3/3!, were evaluated and the Gr{\"u}neisen parameter were calculated. The potential coefficients α and β for Ti-O bond in CaTiO3 are 6.9 eV{\AA}-2 and -38 eV{\AA}-3, respectively. Those for Ge-O bond in CaGeO3 are 9.8 eV{\AA}-2 and -36 eV{\AA}-3, respectively.",

keywords = "Anharmonic effective pair potential, EXAFS Debye-Waller factor, Metastable CaGeO, Perovskite, SrTiO",

author = "Akira Yoshiasa and Kenji Nakajima and Murai, {Kei Ichiro} and Maki Okube",

year = "2001",

month = mar,

day = "1",

doi = "10.1107/S0909049500020689",

language = "English",

volume = "8",

pages = "940--942",

journal = "Journal of Synchrotron Radiation",

issn = "0909-0495",

publisher = "International Union of Crystallography",

number = "2",

}

TY - JOUR

T1 - Anharmonic effective pair potentials in CaTiO3, SrTiO3 and CaGeO3 perovskite

AU - Yoshiasa, Akira

AU - Nakajima, Kenji

AU - Murai, Kei Ichiro

AU - Okube, Maki

PY - 2001/3/1

Y1 - 2001/3/1

N2 - The temperature dependence of EXAFS Debye-Waller factors in CaTiO3, SrTiO3 and CaGeO3 perovskite was investigated with the cumulant expansion method. The CaGeO3 perovskite as an analogue of the Earth's lower-mantle mineral was synthesized in a cubic anvil type apparatus under 10 GPa 1250 K. The Ca, Ti and Ge K-edge EXAFS spectra were measured in transmission mode at temperature up to 1100 K. The effective pair potentials, V(u)= α u2/2+βu3/3!, were evaluated and the Grüneisen parameter were calculated. The potential coefficients α and β for Ti-O bond in CaTiO3 are 6.9 eVÅ-2 and -38 eVÅ-3, respectively. Those for Ge-O bond in CaGeO3 are 9.8 eVÅ-2 and -36 eVÅ-3, respectively.

AB - The temperature dependence of EXAFS Debye-Waller factors in CaTiO3, SrTiO3 and CaGeO3 perovskite was investigated with the cumulant expansion method. The CaGeO3 perovskite as an analogue of the Earth's lower-mantle mineral was synthesized in a cubic anvil type apparatus under 10 GPa 1250 K. The Ca, Ti and Ge K-edge EXAFS spectra were measured in transmission mode at temperature up to 1100 K. The effective pair potentials, V(u)= α u2/2+βu3/3!, were evaluated and the Grüneisen parameter were calculated. The potential coefficients α and β for Ti-O bond in CaTiO3 are 6.9 eVÅ-2 and -38 eVÅ-3, respectively. Those for Ge-O bond in CaGeO3 are 9.8 eVÅ-2 and -36 eVÅ-3, respectively.

KW - Anharmonic effective pair potential

KW - EXAFS Debye-Waller factor

KW - Metastable CaGeO

KW - Perovskite

KW - SrTiO

UR - http://www.scopus.com/inward/record.url?scp=0035293747&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035293747&partnerID=8YFLogxK

U2 - 10.1107/S0909049500020689

DO - 10.1107/S0909049500020689

M3 - Article

C2 - 11512986

AN - SCOPUS:0035293747

VL - 8

SP - 940

EP - 942

JO - Journal of Synchrotron Radiation

JF - Journal of Synchrotron Radiation

SN - 0909-0495

IS - 2

ER -