Structural, thermodynamic, electronic, and optical properties of NaH from first-principles calculations

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	Structural, thermodynamic, electronic, and optical properties of NaH from first-principles calculations
	X. W. Sun; L. C. Cai; Q. F. Chen; X. R. Chen; F. Q. Jing
	2012
发表期刊	Materials Chemistry and Physics
ISSN	0254-0584
卷号	133 期号:1 页码:346-355
摘要	The structural stability, thermodynamic, electronic, and optical properties of NaH with rock salt (B1) structure and cesium chloride (B2) structure under high pressure are investigated by first-principles calculations using norm-conserving pseudopotential applying a generalized gradient approximation (GGA) for exchange and correlation. Through the analysis of energy-volume variation, we find the phase transition of NaH from B1 to B2 structure occurs at 32.3 GPa, which in good agreement with the diamond-anvil-cell high-pressure experimental value of 29.3 +/- 0.9 GPa [Phys. Rev. B 36 (1987) 7664). By using the quasi-harmonic Debye model, the thermodynamic properties including the Debye temperature Theta(D), heat capacity C-V, thermal expansion coefficient alpha, and Gruneisen parameter gamma are successfully obtained in the temperature range from 0 to 700K and pressure ranges from 0 to 32 GPa and 33 to 100 GPa for NaH B1 and B2 phases, respectively. Analysis of band structures suggests that the NaH has an indirect band gap that the valence band maximum is at the W point and the conduction minimum locates at L point. The calculated energy gaps is very close to that value obtained in recent full potential augmented plane wave calculations. The optical properties including dielectric function epsilon(omega), absorption coefficient alpha(omega), reflectivity coefficient R(omega), and refractive index n(omega) are also calculated and analyzed. (C) 2012 Elsevier B.V. All rights reserved.
部门归属	[sun, xiao-wei; cai, ling-cang; chen, qi-feng; jing, fu-qian] china acad engn phys, natl key lab shock wave & detonat phys, inst fluid phys, mianyang 621900, peoples r china. [sun, xiao-wei; chen, xiang-rong; jing, fu-qian] sichuan univ, inst atom & mol phys, sch phys sci & technol, chengdu 610065, peoples r china. [sun, xiao-wei] lanzhou jiaotong univ, sch math & phys, lanzhou 730070, peoples r china. [chen, xiang-rong] chinese acad sci, int ctr mat phys, shenyang 110016, peoples r china.;chen, qf (reprint author), china acad engn phys, natl key lab shock wave & detonat phys, inst fluid phys, mianyang 621900, peoples r china.;sunxw_lzjtu@126.com; chen_qifeng@iapcm.ac.cn
关键词	Ab Initio Calculations Thermodynamic Properties Band Structure Optical Properties Alkali-metal Hydrides Inelastic Neutron-scattering Hydrogen Storage Materials High-pressure Aluminum Hydrides Phase-transitions Quasi-particle Solids Model Approximation
URL	查看原文
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/60248
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	X. W. Sun,L. C. Cai,Q. F. Chen,et al. Structural, thermodynamic, electronic, and optical properties of NaH from first-principles calculations[J]. Materials Chemistry and Physics,2012,133(1):346-355.
APA	X. W. Sun,L. C. Cai,Q. F. Chen,X. R. Chen,&F. Q. Jing.(2012).Structural, thermodynamic, electronic, and optical properties of NaH from first-principles calculations.Materials Chemistry and Physics,133(1),346-355.
MLA	X. W. Sun,et al."Structural, thermodynamic, electronic, and optical properties of NaH from first-principles calculations".Materials Chemistry and Physics 133.1(2012):346-355.