Self-consistent energy bands and bonding ofNi3Si

Abstract

The energy bands of ${\mathrm{Ni}}_3$Si are calculated with the use of the self-consistent linearcombination-of-Gaussian-orbitals method. Partial densities of states are calculated and integrated to find that each Ni atom has 10.3 electrons of which 9.0 are $3d$ electrons. Because there is a gap in the Si $s$ density of states at the Fermi energy, we do not obtain the experimental ${}_{}{}^{29}{}_{}{}^{}\mathrm{Si}$ nuclear-magnetic-resonance relaxation time. The calculated cohesive energy is compared with that of Ni and Si, and a crude estimate of the heat of formation is made. Contour plots of the charge density show the Ni—Si bond to be slightly stronger than the Ni—Ni and also that there is a large metallic component to the bonding.