Electronic structure of molybdenene from first principles

Density functional theory has been applied to investigate the electronic structure and lattice stability of molybdenene monolayer in both its hexagonal and triclinic phases, within ultrasoft pseudopotential approach. In agreement with experimental findings, it has been found that either phase is metallic. Analyzing partial density of states has revealed that the $d$ valence orbitals of molybdenum atoms have had the largest contribution to such a metallic property, due to being half-empty as well as being the outermost. Phonon-dispersion calculations also have led to negative frequencies for either phase, showing lattice instability, as reported in the experimental literature.