First-principles calculations of electronic structure and optical properties of strained Mg2Si

• 来源期刊: 科学通报(英文版)
• 学科: 化学
• 关键词: 第一原理赝势法 Mg2Si 电子结构 光学性质 晶格变形 计算 各向同性 静态介电常数
• 年，卷（期）: 2010,（21）
• 所属期刊栏目: ARTICLES
• 页码范围: 2236-2242
• 页数: 7页
• 分类号: O613.71 TM912.2
• 语种: 英文

摘要

A detailed theoretical study on structural,electronic and optical properties of Mg2Si under the isotropic lattice deformation was performed based on the first-principles pseudopotential method.The results show that the isotropic lattice deformation results in a linear decrease in the energy gap for the directΓ15-Γ1 and indirectΓ15-L1 transitions from 93%to 113%,while the indirect band gapΓ15-X1 increases from 93%to 104%and then reduces over 104%.When the crystal lattice is 93%compressed and 113%stretched,the magnesium silicide is a zero-gap semiconductor.Furthermore,the isotropic lattice deformation makes the dielectric function shift and the static dielectric constant change.