Band structure and optical response of 2H-MoX2 compounds (X=S, Se, and Te) -: art. no. 155114

We report calculations of the electronic and optical properties for the 2H-MoX2 (X=S,Se,Te) compounds using the full potential linear augmented plane wave method within the local density approximation. When S is replaced by Se and Te, the energy gap changes and the bandwidth of the Mo-d bands reduces. From the partial density of states we find a strong hybridization between Mo-d and X-p states below the Fermi energy E-F. On going from S to Se to Te the structures in the frequency-dependent imaginary part of the dielectric function epsilon(2)(omega) shifts towards lower energies. The frequency-dependent reflectivity and absorption show that the plasma minimum also shifts towards lower energies. We compare our calculations with the experimental optical data and find a good agreement.