采用基于密度泛函理论的第一原理赝势平面波方法,计算了LiNH2-X(X=Mg,Al,Ti,Nb)体系的晶体与电子结构及稳定性能.负合金形成热与H原子解离能的计算发现:合金化元素X在LiNH2中少量置换固溶时,体系结构稳定性发生变化,合金化增强了体系的解氢能力,其中Nb提高LiNH2体系解氢效果最好,理论计算预测合金化提高体系解氢性能与他人结果一致.电子态密度(DOS)与电子密度分析发现:X(X=Mg,Al,Ti,Nb)合金化提高LiNH2解氢能力的主要原因是X导致LiNH2体系Fermi能级附近能隙值发生变化以及Li与NH之间的成键作用减弱. The crystal structure and electronic structure of LiNH2-X (X = Mg, Al, Ti, Nb) system were calculated by the first principle pseudopotential plane wave method based on the density functional theory. The heat of negative alloy dissociation The calculated results show that the stability of the system changes when a small amount of alloying element X is substituted and dissolved in LiNH2, and alloying enhances the ability of the system to desorb the hydrogen. In addition, Nb improves the hydrogen desorption effect of the LiNH2 system. The theoretical calculation and prediction alloy The results of DOS and electron density analysis showed that the main reason for X (X = Mg, Al, Ti, Nb) alloying to improve the ability of hydrogen desorption of LiNH2 is that X lead to LiNH2 system Changes in the energy gap near the Fermi level and the weakening of the bonding between Li and NH.