Hydrogen site occupation and electronic structure in the La₂Ni₂In intermetallic and hydrides

Abstract

By means of electronic structure computation methods based on density functional theory, we investigated some properties of the intermetallic compounds R 2 Ni 2 In (R ¼ La, Ce, Pr, Nd). We studied the hydrogen atom occupancy in the La 2 Ni 2 In intermetallic and we found that the available interstitial sites for hydrogen occupation can be clearly differentiated by the hydrogen site energy. Hydrogen atoms are stabilized by the NiAH bonding interaction. This result indicates that the formation of a solid solution and eventually a hydride phase follow an enthalpic controlled order. With this information, we have investigated the formation of hydride phases in La 2 Ni 2 In.