第一性原理计算研究V2AlX(X=C、N)相的热力学性能
Thermodynamic Properties of V2AlX(X=C,N)Phase Researched by First-principles Calculation
黄大建 1史沛然 1法涛1
作者信息
- 1. 表面物理与化学重点实验室,四川 绵阳 621908
- 折叠
摘要
通过第一性原理基于 PAW 方法研究了 V2AlX(X=C、N)相的结构、电子、声子和热力学性质.讨论了V2AlX(X=C、N)相的结构和电子特性;利用晶格动力学的超晶胞方法计算了声子色散曲线,并通过准简谐近似预测高温下V2AlX(X=C、N)相的热力学性质.结果表明:V2AlC和V2AlN具有金属性,且用N原子置换C原子后费米面处的态密度减低.V2AlC和V2AlN都是动力学稳定的.此外,还发现V2AlN相的热力学性质比V2AlC的更优异,且V2AlN的体模量也高于V2AlC.
Abstract
The structure,electronic,phonon and thermodynamic properties of V2AlX(X=C or N)were investigated by first-principles calculations using PAW method.The structural and electronic properties of the V2AlX(X=C or N)were discussed.The supercell method of lattice dynamic was utilized to calculate the phonon dispersion curves,and the thermodynamic properties of the V2AlX(X=C or N)phase at elevated temperatures were predicted by quasiharmonic approximation.The results show that V2AlC and V2AlN have metallicity and the replacement of N atoms for C atoms can result in the decrease in the DOS at Fermi level.Both the ternary MAX phases V2AlC and V2AlN are dynamically stable.Furthermore,it is found that the thermodynamic properties of V2AlN are more excellent compared with that of V2AlC phase,and the bulk modulus of V2AlN is also higher than that of V2AlC.
关键词
V2AlX/电子/声子/热力学性能Key words
V2AlX/electronic/phonon/thermodynamic properties引用本文复制引用
基金项目
科学挑战计划(JCKY2016212A504)
出版年
2024
NETL
NSTL
万方数据