Density functional theoretical study of lattice-specific heat and thermal properties of magnesium nitride

摘要

A comprehensive first principle study of thermodynamic properties of MgN is reported within the density functional theory scheme. The ground state properties such as lattice constant, Bulk modulus etc. of MgN in rock-salt (RS) phase have been determined. The thermodynamical properties have been analyzed in the light of phonon density of states of MgN and its constituent atoms. The variation of lattice-specific heat with temperature obeys the classical Dulong–Petit’s law at high temperature while at low temperature it obeys Debye T 3 law. The phonon spectrum shows the presence of all positive phonons and zero phonon density of states at zero energy confirming a dynamically stabilized structure of MgN in RS phase.