Theoretical study of structure and stability of fullerene derivative: C50O

A total of eight possible isomers of C50O, an oxide of fullerene C50 (D5h), have been investigated by B3LYP/3-21G calculations. The isomer, which has an annulene-like structure with oxygen bridging across a [5,6] type CC bond at the site between the pole and the equatorial belt, is found being the ground state of C50O. Four isomers are relatively more stable and the energy differences between them are not large. This result indicates that more than one C50O isomer will coexist once C50O is synthesized. The relative stabilities of the C50O isomers may be determined mainly by the strain release and by the formation of the cyclic phenylene substructure at the equatorial belt of the cage. The calculated nucleus independent chemical shifts (NICS) of the C50O isomers will be useful because from them one can expect outstanding NMR properties that can lead to their identification and characterization. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005