LiNH2晶体结构和电子结构的第一性原理研究

采用基于密度泛函理论的赝势——平面波方法,应用LDA的CA-PZ泛函和GGA的PBE、RPBE和PW91泛函对LiNH2晶体结构进行优化,计算电子结构.结果表明,GGA-PW91泛函更适于描述LiNH2晶体的结构和性质.LiNH2晶体为四面体结构,空间群I-4,晶格常数a=b=0.501 9 nm,c=1.034 9 nm,N-H键长为0.103 1 nm,H-N-H键角为103°.电子态密度和电子局域密度分析表明,N-H键呈明显的共价键特性,Li和N-H之间为离子键相互作用.

Study on the First Principle of Crystal Structure and Electronic Structure of Lithium Amide

The crystal structure and electronic structure of Lithium amide(LiNH2) are studied by employing the first-principle plane wave pseudopotential method based on the density function theory(DFT).The local density approximation(CA-PZ) and the generalized gradient approximation(PBE,RPBE and PW91)are applied for structure optimization.The calculated results show that GGA-PW91 function is more suitable than others in dealing with LiNH2 problem.The crystal structure of LiNH2 is tetragonal(space group I-4).The latti...