Effect of the accumulation of excess Ni atoms in the crystal structure of the intermetallic semiconductor $n$-ZrNiSn

The crystal structure, electron density distribution, and energy, kinetic, and magnetic properties of the $n$-ZrNiSn intermetallic semiconductor heavily doped with a Ni impurity are investigated. The effect of the accumulation of an excess number of Ni$_{1 + x}$ atoms in tetrahedral interstices of the crystal structure of the semiconductor is found and the donor nature of such structural defects that change the properties of the semiconductor is established. The results obtained are discussed within the Shklovskii–Efros model of a heavily doped and strongly compensated semiconductor.