Qing-Bo Yan, Qing-Rong Zheng, Gang Su*
College of Physical Sciences, Graduate University of Chinese Academy of Sciences, P.O. Box 4588, Beijing 100049, China
Received 18 November 2006; accepted 28 April 2007
Available online 18 May 2007
Abstract:
The geometrical structures, electronic properties, and spectroscopies of non-IPR (isolated pentagon rule) fullerene C 66 and its derivatives C 66 X 4 (X = H, F, Cl) have been studied by the first-principle calculations based on the density functional theory. By searching through all 4478 isomers of C 66 , the ground state of C 66 is observed to bear C s symmetry and have two pairs of fusion pentagons. It is found that the addition of H, F, Cl atoms to the pentagon–pentagon fusion vertex of C66 cages can form new non-IPR fullerenes such as C66 X4 , where the molecule C66 X 4 with C 2v symmetry are uncovered to be the most stable among others. The Mulliken charge populations, gap energies between the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO), and density of states of these unconventional fullerenes are calculated, showing that different atoms added to non-IPR C 66 cages will alter the charge populations remarkably; the chemical deriving could affect the electronic structures distinctly, and improve the stability of the fullerenes. The calculated results of IR, Raman, NMR spectra of C 66 X 4 are also presented.