Eur. Phys. J. B 73, 185-193 (2010)
https://doi.org/10.1140/epjb/e2009-00426-6

Ab initio lattice dynamics and piezoelectric properties of MgS and MgSe alkaline earth chalcogenides

¹ Physics Department, Faculty of Science and Engineering, University of M'sila, 28000 M'sila, Algeria
² Department of Physics, Faculty of Science, King Khalid University, Abha, P.O. Box 9004, Saudi Arabia
³ MALTA Consolider Team, Departamento de Física Fundamental II, and Instituto de Materiales y Nanociencia, Universidad de La Laguna, La Laguna 38205, Tenerife, Spain

Corresponding author: n_bouarissa@yahoo.fr

Received: 3 February 2009
Revised: 25 August 2009
Published online: 24 December 2009

Abstract

We have studied structural, elastic, dielectric, vibrational, and piezoelectric properties of rock-salt and zinc-blende Mg alkaline earth chalcogenides (MgS, and MgSe) by using the plane-wave pseudopotential method within the local density approximation. The calculated lattice constant, bulk modulus, and elastic constants for these compounds are found to be in good agreement with experiment. The density functional perturbation theory has been employed to derive the Born effective charge and high-frequency dielectric constant and to calculate phonon dispersion curves and density of states. The piezoelectric constant has also been determined. The calculated results are compared with theory and experiment when available and showed reasonable agreement. In other cases, our results are predictions. The pressure dependence of the studied quantities has been examined and discussed. The pressure coefficients and mode Grüneisen parameters are determined.