物理学报2012，Vol.61Issue(4)：332-343,12.
Cr_2MC（M=Al,Ga）的电子结构、弹性和热力学性质的第一性原理研究
First-principles investigations on the electronic,elastic and thermodynamic properties of Cr_2MC（M=Al,Ga）
摘要
Abstract
We investigate the electronic,elastic and thermodynamic properties of nanolaminate Cr_2MC（M=Al,Ga） by using the ab initio pseudopotential total energy method.Our results show that they have shown almost identical volume compressibilities.The axial compressibility investigations show that the c axis is always stiffer than a axis.The internal coordinate calculations revealed that the values of Cr atoms in Cr_2AlC are always larger than those in Cr_2GaC.The elastic constants calculations demonstrated the structural stability within 0—50 GPa.The obtained bulk moduli by quasi-harmonic Debye model observed that the bulk moduli of Cr2MC（M=Al, Ga）decrease with temperature at 0 GPa,but increase at 300 GPa.We also found that the Debye temperatures of Cr_2GaC are always smaller than those of Cr_2A1C at any conditions.However,the opposite cases can be found in thermal expansion coefficients,Griineisen parameter,entropy and heat capacity when comparing their respective counterparts between Cr_2GaC and Cr_2AlC.The electronic density of states and energy band distribution demonstrated that the Cr_2MC（M=Al,Ga） have shown similar profiles with the only exception of the more localized s and p electrons in Cr_2GaC than their respective counterparts in Cr_2AlC.关键词
第一性原理/电子结构/弹性/热力学性质Key words
first-principles/electronic structure/elasticity/thermodynamic properties分类
化学化工引用本文复制引用
杨则金,令狐荣锋,程新路,杨向东..Cr_2MC（M=Al,Ga）的电子结构、弹性和热力学性质的第一性原理研究[J].物理学报,2012,61(4):332-343,12.基金项目
国家自然科学基金 （）
贵州省科学技术基金 （）
贵州省高层次人才科研条件特助项目 （）
浙江省教育厅科研项目（批准号：Y201 121807）资助的课题 （）
