First-principles Study on the Structural, Electronic, and Elastic Properties of Transition Metal Dichalcogenides

In this paper, the structural, electronic, and elastic properties of molybdenum disulfide (MoS2) in hexagonal and trigonal phases were investigated using first-principles calculations based on density functional theory (DFT) as implemented in the Quantum ESPRESSO package. Our findings from the structural and electronic properties of MoS2 show that bulk hexagonal and trigonal MoS2 phases have a calculated bandgap of 1.37 and 1.56 eV respectively, which is in good agreement with available theoretical and experimental results. The elastic properties show that both space groups of MoS2 are brittle at zero pressure and they also agree with Born's mechanical stability condition. The overall results place our new optimized MoS2 as a potential candidate for optoelectronic application.