Ground state and phonon spectrum of NiSi₂

Abstract

We have studied structural, electronic, elastic and dynamical properties of NiSi₂ 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 first-principles calculations of the elastic constants were used to calculate C₁₁, C₁₂ and C₄₄ for NiSi₂. 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 NiSi₂ at the Γ, X and L symmetry points are also presented.

Keywords:

• NiSi₂
• electronic stucture
• elastic properties
• phonons

Acknowledgement

This work was supported by the Yuzuncu Yıl University Research Project Unit under Project No. 2008-FED-B090 and the computations were partly performed at the TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure).