Investigation of Phononic and thermal properties of Gallium Phosphide in two Zincblend and hexagonal phases

Document Type : Original Article

Authors

• Hamdollah salehi
• shiva mokhavat
• Peiman Amiri

Department of Physics, Faculty of Science,ShahidChamran University,of Ahvaz,Ahvaz,Iran

Abstract

IIn this paper, the phononic , thermal properties and pressure transition of GaP in
two stable phases, Zincblend and Cinnabar phase, have been investigated.
Calculations were performed by using the pseudo-potential method in the framework of the density functional theory and using the Quantum Espresso code.The pseudopotentials applied here are generated using norm-conserving condition within GGA is used to calculate the exchange-correlation potential.The Energy –Volume diagram at the pressure transition shows that the cinnabar phase is metastable.
The phonon scattering diagram shows that this compound has a gap between 242 cm-1 up 311 cm-1 in the Zincblend and there is no gap in the cinnabar phase.
From the study of the thermodynamic properties of the two phases of Zincblend and Cinnabar, we find that in both phases, the drop in heat capacity at low temperatures is .At high temperatures, the heat capacity become close to (Dulong –Petit law).

Keywords

• Gallium Phosphide
• density functional theory
• phonon modes
• Thermal properties

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