Stabilities, electronic properties of exohedral fluorine and trifluoromethyl derivatives for T-d C-28 fullerene C28F4-n(CF3)(n) (n=0,1,2,3,4)

摘要

Stability and electronic property calculations are performed systematically based on density functional theory at the B3LYP/6-31G(d) level for T-d C-28 fullerene and exohedral fluorine and trifluoromethyl derivatives C28F4-n(CF3)(n) (n = 0,1,2,3,4). All the exohedral derivatives that are on the potential energy surfaces are kinetically stable with large HOMO-LUMO gaps. Further investigations show that binding energies of C28F4-n(CF3)(n) (n = 0,1,2,3,4) molecules are positive, suggesting they are thermodynamically stable. An analysis of the pi-orbital axis vector indicates the high strain in T-d C-28 cage could be greatly released by fluorine and trifluoromethyl decorations. Mulliken charge analysis reveals that adding different electron groups to the T-d C-28 cage can cause remarkably different charge populations. In addition, from the ionization potential and electron affinity investigations, the C28F4-n(CF3)(n) (n = 0,1,2,3,4) molecules manifest weak redox properties. (C) 2008 Wiley Periodicals, Inc.