Electronic properties of Hf2X intermetallic compounds (X = Al, Si, Ni, Ga and Ge)

Abstract

The electric field gradient (EFG) parameters were calculated for the binary system Hf2X (X = Al, Si, Ni, Ga and Ge), using the full-potential linear augmented plane wave method, applying the generalized gradient approximation. The major contribution to the EFG value in these compounds comes from the p–p contribution next to the probe nucleus. The only other significant contribution is a d–d contribution to the nickel site in Hf2Ni, arises from the broad spatial distribution of the nickel 3d electrons. The similarity in the electronic properties of the Hf2X compounds, with the exception of Hf2Ni, can be attributed to the resemblance of the crystallographic structure and the alike electronic structure of the X-ligand atom, having one or two p-electrons in the external orbital with close shells below.