Theoretical elastic stiffness, structure stability and thermal conductivity of La2Zr2O7 pyrochlore

被引：138

作者：

Liu, B.

Wang, J. Y. ^{[1
]}

Zhou, Y. C.

Liao, T.

Li, F. Z.

机构：

[1] Chinese Acad Sci, Shenyang Natl Lab Mat Sci, Inst Met Res, Shenyang 110016, Peoples R China

[2] Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China

[3] Chinese Acad Sci, Inst Met Res, Int Ctr Mat Phys, Shenyang 110016, Peoples R China

来源：

ACTA MATERIALIA | 2007年 / 55卷 / 09期

基金：

中国国家自然科学基金;

关键词：

density functional theory (DFT); local density approximations (LDA); electronic structure; mechanical properties; thermal conductivity;

D O I：

10.1016/j.actamat.2006.12.035

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Elastic stiffness and electronic structure of La2Zr2O7 were calculated by means of the first-principles pseudopotential total energy method. The equation of state (EOS), elastic parameters (including the full set of second-order elastic coefficients, bulk modulus and Young's modulus) and elastic anisotropy were reported. Furthermore, pressure dependence of crystal structure, electronic structure, and bond strengths were investigated. It is found that, although the La2Zr2O7 lattice is stable at high pressures, its electronic structure and atomic bonding are definitely disturbed by the applied pressure. The crystal structure of La2Zr2O7 approaches that of the fluorite-type lattice at high pressures. The strengths of different interatomic bonds in La2Zr2O7 are examined by considering bond-length contractions at various pressures. In addition, the results based on quantum-mechanical-scale calculation clarify the nature of low thermal conductivity of La2Zr2O7 at elevated temperatures. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：2949 / 2957

页数：9

共 34 条

[1] Structural and mechanical properties of TaZrN films: Experimental and ab initio studies [J].