Investigation of Some Physical Properties of CoAsS Crystal Under Pressure

Abstract

Density functional theory (DFT) within the generalized gradient approximation (GGA) was used to inquire the structural, electronic, optical, elastic and thermodynamic properties of CoAsS crystal for the ground state (P=0 GPa) and for some pressure values such as 10, 20, 30, 40 and 50 GPa. CoAsS crystal has a semiconductor character with 1.06 eV indirect band gap. By increasing the pressure on CoAsS crystal band gap values were increasing as expected but by 40 GPa band gap value intented to decrease because of the structural deformation caused by the high pressure. The graphs of electronic band structure, density of states, and the all graphs for optic and thermodynamic properties were plotted with all pressure values and given in one figure to provide an easy comparison. Elastic properties were also given to show the effect of pressure on CoAsS crystal. It was noticed that cubic CoAsS mineral was fragile.