The influence of lattice deformation on the elastic properties of Mg_2Si  

作　　者：CHEN Qian XIE Quan XIAO QingQuan ZHANG JinMin 

机构地区：[1]College of Science, Guizhou University [2]Institute of New Optoelectronic Materials and Technology, Guizhou University

出　　处：《Science China(Physics,Mechanics & Astronomy)》2013年第4期701-705,共5页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the Young Talents Training Project of Guizhou Province (Grant No. [2012]152);the National Natural Science Foundation of Guizhou Province (Grant No. [2011]2323);the Introducing Talents Foundation for the Doctor of Guizhou University (Grant No.[2010]032);the National Natural Science Foundation of China (Grant No.61264004);the Special Fund for International Cooperation of the Ministry of Science and Technology of China (Grant No. 2008DFA52210);the Key SciTech Research Project of Guizhou Province of China (Grant No.[2011]3015);the Special Fund for Construction of SciTech Innovative Talents Team of Guizhou Province of China (Grant No. [2011]4002);the Fund for International SciTech Cooperation of Guizhou Province of China (Grant No. [2012]7004)

摘　　要：A detailed theoretical study of the structural and elastic properties of magnesium silicide Mg2 Si under isotropic lattice deformation has been performed based on the first-principles' pseudopotential method. The results show that isotropic lattice deformation from 94% to 106% results in a linear decrease in the energy gap for the direct Г15-Г1 and indirect Г15-L1 transitions, while the indirect band gap Г15 -X1 increases within a range of 94%-104%, and then reduces over the range of 104%. Additionally, isotropic lattice deformation from 94% to 106% also causes a decrease in the elastic constants and modulus of Mg2 Si. Furthermore, Mg2 Si with lattice deformation from 94% to 106% is brittle, being most brittle at 94% lattice constant.A detailed theoretical study of the structural and elastic properties of magnesium silicide Mg2 Si under isotropic lattice deformation has been performed based on the first-principles’ pseudopotential method. The results show that isotropic lattice deformation from 94% to 106% results in a linear decrease in the energy gap for the direct Г15-Г1 and indirect Г15-L1 transitions, while the indirect band gap Г15 -X1 increases within a range of 94%–104%, and then reduces over the range of 104%. Additionally, isotropic lattice deformation from 94% to 106% also causes a decrease in the elastic constants and modulus of Mg2 Si. Furthermore, Mg2 Si with lattice deformation from 94% to 106% is brittle, being most brittle at 94% lattice constant.

关 键 词：magnesium silicide lattice deformation FIRST-PRINCIPLES band structure elastic properties 

分 类 号：TN304[电子电信—物理电子学]