BiOCuS电子结构、化学键和弹性性质的第一性原理研究(英文)

• 作 者: 潘留仙 夏庆林 叶绍龙 丁宁 刘自然
• 机 构: 湖南涉外经济学院电气与信息工程学院,中南大学物理与电子学院,中南大学冶金科学与工程学院,
• 出 处: Transactions of Nonferrous Metals Society of China
• 发表日期: 2012年05期
• 关键词: BiOCuS 第一性原理 电子结构 化学键 弹性性质 间接带隙半导体 费米能级 广义梯度近似 密度泛函理论 tetragonal

利用基于密度泛函理论(DFT)的广义梯度近似(GGA)研究四方相BiOCuS的电子结构、化学键和弹性性质。能带结构显示,BiOCuS为间接带隙半导体,带隙宽为0.503eV;态密度和分态密度的结果表明,费米能级附近的态密度主要来自Cu-3d态。布居分析表明,BiOCuS中的化学键具有以离子性为主的混合离子?共价特征。计算得到四方相BiOCuS的晶格参数、体模量、剪切模量和单晶的弹性常数,由此导出弹性模量和泊松比。结果表明,BiOCuS是力学稳定的,且具有一定的延展性。

The electronic structure, chemical bonding and elastic properties of tetragonal BiOCuS were studied by using the generalized gradient approximation (GGA) based on density functional theory (DFT). The band structure shows that BiOCuS is an indirect bandgap semiconductor with a bandgap width of 0.503eV. The results of the state density and the density of states indicate that the state density near the Fermi level mainly comes from the Cu-3d state. The population analysis shows that the chemical bonds in BiOCuS have the characteristic of covalent ion-dominated mixed ions. The lattice parameters, bulk modulus, shear modulus and single-crystal elastic constants of tetragonal BiOCuS were calculated and the elastic modulus and Poisson’s ratio were derived. The results show that BiOCuS is mechanically stable and has some ductility.