Tuning electronic and magnetic properties of endohedral Co@B80 and exohedral Co-B80 metallofullerenes by positioning Co atom

Abstract

We have performed a systematical study of the structural configurations, electronic and magnetic properties of the single Co-doped endohedral Co@B80 and exohedral Co–B80 metallofullerene complexes using spin-polarized density functional calculations. Our calculations revealed that there are four stable configurations of the Co-doped metallofullerenes depending on different positions of the doping Co atoms as follows. In the case of the exohedral Co–B80 metallofullerene complexes, Co atom energetically prefers standing near the centers of pentagon (pentagon-out) and hexagon (hexagon-out) on the surface of B80. In the case of the endohedral Co@B80 metallofullerene complexes, the encapsulated Co atom energetically prefers standing near the centers of pentagon (pentagon-in) and hexagon (hexagon-in) on the inner surface of the hollow cage of B80. Electronically, the energy gaps of the hexagon-near adsorbed metallofullerenes have been greatly modified compared with that of B80. At the same time, the magnetic moments of both of the exohedral Co–B80 metallofullerenes are one third of that of the isolated Co atom. The tunable electronic and magnetic properties of the Co-doped B80 metallofullerenes clearly showed that this new type of metallofullerenes may be a promising candidate for molecular devices, especially single molecular spin electronic devices.