五氢化镉高压新相的理论研究  

Theoretical investigations of a new high-pressure phase of cadmium pentahydride

作　　者：闫岩[1] 彭阳明 张王颖 刘朝厅 YAN Yan;PENG Yang-ming;ZHANG Wang-ying;LIU Chao-ting(College of Science,Changchun University,Changchun 130022,China)

机构地区：[1]长春大学理学院,吉林长春130022

出　　处：《吉林师范大学学报（自然科学版）》2023年第2期18-24,共7页Journal of Jilin Normal University:Natural Science Edition

基　　金：吉林省科技发展计划项目(20190201127JC);长春大学“长大学者攀登计划”项目(zkp202033)。

摘　　要：基于粒子群优化算法和第一性原理相结合,对CdH_(5)的高压新相P2_(1)相在压强P=300 GPa时的晶体结构、电子能带、电子态密度和晶格动力学等性质展开了系统地研究.结果表明,该高压相在压强P=300 GPa时表现为金属性,晶格动力学稳定.在结构中H原子是以H_(2)单元的形式存在,H—H键长接近于氢分子的键长(约为0.07 nm).P2_(1)相中Cd—H间没有电子局域呈离子键,而H—H间则呈共价键,电子从Cd原子转移到H_(2)单元.The crystal structure,electronic band structure,electronic density of states and dynamical stability of the new high-pressure P2_(1) phase of CdH_(5) at 300 GPa were systematically studied using the structural prediction based on particle swarm optimization algorithm and first principles based on density functional theory.The results show that this high-pressure phase is metallic at 300 GPa,and the lattice dynamics are stable.In this structure,the H atom exists in the form of H_(2) unit,and the H—H bond length is close to the bond length of the hydrogen molecule(about 0.07 nm).In the P2_(1) phase,there are ionic bonds between Cd and H atoms,but covalent bonds between H and H atoms.The electrons are transferred from Cd atom to H_(2) unit.

关 键 词：氢化物 高压 晶格动力学 第一性原理 

分 类 号：O474[理学—半导体物理]