Chemical bonding and elastic properties of quaternary arsenide oxides YZnAsO and LaZnAsO investigated by first principles  

四元砷氧化物YZnAsO和LaZnAsO的化学键和弹性性质的第一性原理研究(英文)

作　　者：施毅敏[1] 叶绍龙[2] 

机构地区：[1]湖南工学院基础教学部,衡阳421000 [2]中南大学冶金科学与工程学院,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第6期1378-1382,共5页中国有色金属学报（英文版）

基　　金：Project(50474051)supported by the National Natural Science Foundation of China

摘　　要：The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory （DFT） within generalized gradient approximation （GGA）. The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill＇s approximations （VRH）. The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear.利用基于密度泛函理论(DFT)的广义梯度近似(GGA)研究四方相四元砷氧化物YZnAsO和LaZnAsO的结构参数、化学键和弹性性质。结果表明,GGA计算的结构参数与实验值吻合较好。布居分析显示YZnAsO和LaZnAsO中的化学键具有混合的离子-共价特征。计算得到了单晶的弹性常数,由Voigt,Reuss和Hill(VRH)近似导出了多晶弹性模量,结果表明YZnAsO和LaZnAsO为具有一定延展性、相对较软的材料。多晶的弹性各向异性结果显示,LaZnAsO的体模量各向异性相对较大,而YZnAsO的剪切模量各向异性相对较大。

关 键 词：YZnAsO LaZnAsO chemical bonding elastic properties density-functional theory generalized gradientapproximation Voigt  Reuss and Hill＇s approximations 

分 类 号：TG111.1[金属学及工艺—物理冶金]