(color online) Schematic diagram of molecular orbitals of the V adatom, where the left part shows the orbitals of a free V atom, the middle part refers to those orbitals in C _3v local symmetry, and the right part denotes the molecular orbitals corresponding to the mid-gap states in Figs. 5(a) and 5(f). Note only the molecular orbitals of V-group are shown here.