Ab initio study of structural, electronic, and magnetic properties of V _n (C ₆₀) _m Complexes

We have studied structural, electronic, and magnetic properties of transition-metal-fullerene complexes Vn(C60)m,(n, m) = (1, 1), (1, 2), (2, 3), (3, 4), (4, 4), by means of a density functional theory method. We have examined relative stabilities of complexes with different V-C60 binding sites (V atoms are bound to either pentagonal or hexagonal rings of C60) and with different stacking configurations (linear or nonlinear). The linearly stacked sandwichlike complexes with V atoms binding to hexagonal rings of C60 are the most stable for (n, m) = (n, n + 1), although nonlinearly stacked configurations can be energetically competitive. For (n, m) = (1, 1), the V atom tends to bind to a pentagonal ring of the C60 molecule. For (n, m) = (4, 4), a riceball-like structure is found to be the most stable. Except for (n, m) = (1,1), the lowest-energy structures of the complexes are generally in their lowest spin states.