The geometry optimization and electronic structure calculations of the TMD system were performed using the projector augmented wave (PAW) formalism within the framework of density functional theory (DFT). The calculations were carried out using the QUANTUM Espresso package . To describe the exchange and correlation functional, the Perdew-Burke-Ernzerhof (PBE) generalized-gradient approximation (GGA) was employed . In addition to the GGA, several exchange-correlation functionals were employed, including van der Waals density functionals, to accurately account for the weak vdW interactions. In this study, the TMD system was considered to exhibit semiconductor behavior in the 2H phase, while it was expected to be metallic in the 1T phase. To obtain optimized geometry structures and electronic states, the most accurate and effective functionals were selected for the isolated system. The plane-wave cut-off energy was set to 480 eV, ensuring convergence in the calculations. Moreover, a vacuum space larger than 12 was employed to eliminate any spurious interactions between adjacent slabs.