quantum espresso code

In this research, we investigate the effects of pressure and enthalpy on the composition of molybdenum disulfide in the framework of the density functional theory and with the Espresso quantum code with flat waves and the exchange potential of the generalized slope approximation of the stationary charge. The lattice constants of the hexagonal structure of molybdenum disulfide compound were calculated and compared with other works and we have seen the agreement of the results. The electronic properties of the compound were plotted and calculated for comparison with pressure application. The band structure of molybdenum disulfide shows the semiconducting nature with a gap of about 2.27 electron volts, which is larger than the results of other researches. The density of states is plotted for the molybdenum disulfide compound and confirms the semiconducting nature of the compound. The gap obtained from the density of states is more consistent with the results of other works and its value is about 1.3 electron volts. It draws the density of partial states and shows the role of d orbital of molybdenum atom and p of sulfur atom in the overall state density. In the following, we apply different pressures, by applying constant positive pressures, the network increases, and first the bandgap decreases, then increases a little in energy, and then decreases again until the structure changes from a semiconducting nature to a metal, and by applying pressures. The lattice constant negativity is reduced and the bandgap is reduced, and in the same application of the initial pressures, it is out of the semiconducting nature and tends towards the metallic property.