Bond and atomization energies of C 60 and C 70 fullerenes

Abstract

The bond (BE) and atomization energies ( E 0 at ) of C 60 and C 70 fullerenes are predicted by the theoretical BELE partitioning method which uses information derived from the electronic charge density at bond critical points and from the length of the curve of maximum charge density between two bonded atoms (bond path). The nuclear geometries and electronic charge densities are obtained from Kohn-Sham density functional calculations employing a TZP AO basis and the non-local BLYP exchange-correlation functional. The predicted atomization energies at 0 K of C 60 and C 70 are 9765 kcal mol −1 (exp.: 9762–9797 kcal mol −1) and 11437 kcal mol −1 (exp.: 11455 kcal mol −1), respectively. The BE values of the six-six ring and the five six ring bonds of c 60are 118.9 and 103.3 kcal mol −1. The C 70 molecule shows a broader BE distribution ranging from 97.5 to 120.3 kcal mol −1. The results of the fullerenes are compared with corresponding data of benzene (BE = 120.3 kcal mol −1) and C 5 H 5 − ( BE = 110.9 kcal mol −1) as aromatic model compounds. From the C 60 and C 70 data a linear BE bond lengths relationship in fullerenes is established.