Vibrational Entropy Stabilizes Distorted Half-Heusler Structures

doi:10.1021/acs.chemmater.0c01404

	Vibrational Entropy Stabilizes Distorted Half-Heusler Structures
	Guo, Shuping 1,2,3; Anand, Shashwat 3; Zhang, Yongsheng 1,2; Snyder, G. Jeffrey 3
刊名	CHEMISTRY OF MATERIALS
	2020-06-09
卷号	32
ISSN号	0897-4756
DOI	10.1021/acs.chemmater.0c01404
通讯作者	Zhang, Yongsheng(yshzhang@theory.issp.ac.cn) ; Snyder, G. Jeffrey(jeff.snyder@northwestern.edu)
英文摘要	First-principles methods have been extensively used for prediction of half-Heusler (HH) phases for a wide range of functional properties. However, in some cases, suggested stable HHs are observed to be distorted phases (P6(3)mc or Pnma) in experiments. We examine the impact of vibrational entropy on the thermodynamics of HH and competing low-symmetry phases by performing phonon calculations. We find that, in general, the lower symmetry phases have larger vibrational entropies, favoring their stability at higher temperatures. The high vibrational entropy of the distorted phase possibly comes from the weak bonding associated with larger atom motion, which leads to a large phonon density of states at low frequency. Our work explains the discrepancy between first-principles predictions and experimental phase stability and emphasizes the important effect of including vibrational entropy on the phase stability.
资助项目	National Natural Science Foundation of China[11774347] ; National Natural Science Foundation of China[DE-AC02-76SF00515] ; U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) ; China Scholarship Council (CSC)
WOS关键词	CRYSTAL
WOS研究方向	Chemistry ; Materials Science
语种	英语
出版者	AMER CHEMICAL SOC
WOS记录号	WOS:000541499600038
资助机构	National Natural Science Foundation of China ; U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) ; China Scholarship Council (CSC)
内容类型	期刊论文
源URL	[http://ir.hfcas.ac.cn:8080/handle/334002/92845]
专题	中国科学院合肥物质科学研究院
通讯作者	Zhang, Yongsheng; Snyder, G. Jeffrey
作者单位	1.Chinese Acad Sci, Inst Solid State Phys, Key Lab Mat Phys, Hefei 230031, Peoples R China 2.Univ Sci & Technol China, Sci Isl Branch, Grad Sch, Hefei 230026, Peoples R China 3.Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA
推荐引用方式 GB/T 7714	Guo, Shuping,Anand, Shashwat,Zhang, Yongsheng,et al. Vibrational Entropy Stabilizes Distorted Half-Heusler Structures[J]. CHEMISTRY OF MATERIALS,2020,32.
APA	Guo, Shuping,Anand, Shashwat,Zhang, Yongsheng,&Snyder, G. Jeffrey.(2020).Vibrational Entropy Stabilizes Distorted Half-Heusler Structures.CHEMISTRY OF MATERIALS,32.
MLA	Guo, Shuping,et al."Vibrational Entropy Stabilizes Distorted Half-Heusler Structures".CHEMISTRY OF MATERIALS 32(2020).