Ground state and phonon spectrum of NiSi₂

Abstract

We have studied structural, electronic, elastic and dynamical properties of NiSi 2 by employing the plane wave pseudopotential method based on density functional theory within the local density approximation. The calculated lattice constant, bulk modulus and first-order pressure derivative of the bulk modulus are reported and compared with earlier available experimental and theoretical calculations. Numerical firstprinciples calculations of the elastic constants were used to calculate C 11 , C 12 and C 44 for NiSi 2 . The calculated electronic band structure has been compared with angle-resolved photoemission spectroscopy experimental data along the [100] and [111] symmetry directions. A linear response approach to density functional theory is used to derive the phonon dispersion curves and phonon partial density of states. Atomic displacement patterns for NiSi 2 at the À, X and L symmetry points are also presented.