Structures, stabilities and electronic properties of C50 dimers

The dumbbell-shaped dimers constructed from C-50 cages are investigated using self-consistent field molecular orbital method based on density functional theory. Our study focuses on the structures, stabilities, electronic and vibrational properties of the C-50 dumbbell-shaped dimers. It is found that the stability of these C-50 dimers is related to bonding positions and linking patterns. For the dimers by [2 + 2] cycloaddition, a simple rule is proposed to predict the stabilities of these additive products of fullerenes according to the environment around the C-C bonds on the addition position. Moreover, higher thermodynamic stability is accompanied with larger HOMO-LUMO gaps for these dimers. The vibrational properties of the C-50 dimers are also discussed in this paper. (C) 2010 Elsevier B.V. All rights reserved.