LiH晶体的几何结构及电子结构

Geometric and Electronic Structure of LiH Crystal

用CASTEP中的GGA/RPBE基组优化了LiH晶胞的几何结构,并用超软赝势平面波方法计算了LiH晶体的总能量.结果表明,其晶胞参数优化结果为0.4012nm,该数据与文献值相比,相对误差仅为-0.15%;通过对优化后的LiH晶体进行总态密度图和分波态密度图及Mulliken电荷分析,发现Li原子的p轨道有电子分布,即Li的s、p轨道均参与了成键,这表明LiH晶体中有sp轨道杂化;成键时电子的重叠增强,LiH晶体的共价性增加.

The geometric structure of LiH lattice cell was optimized by using soft ware CASTEP with the GGA-RPBE, and the total energy of LiH crystal was ealculated through ultmsoft pseduopotential（USP） plane wave method in this paper. The results show that the lattice cell parameter of optimization is 0.4012 nm, which has only-0.15% relative error （RE） compared with the results from the literatures. Based on the analyses of the total and the partial state density figures and Mulliken charge of optimized LiH crystal, it is found that there is charge distribution in the p orbit of lithium atom, that means both the s and p orbit of lithium participate in bonding. Then the following can be concluded that there exists sp hybridization in LiH crystal, enhancement on the overlap of electron cloud and covalence of LiH crystal in bonding.