Abstract: Based on the first-principles calculation,density functional theory-generalized gradient approximation(DFT-GGA) and the full potential linear augmented plane wave(FLAPW) method,the equilibrium structure、charge density and density of states are calculated for the primary solid solution phase α-LaNi4.5Al0.5H0.5.It is calculated from the view of the energy that H atom is most likely to take the 6m position near Al atom.The pictures of DOSs and charge densities are also given.The results calculated exactly agre...