Ab initio studies on the molecular electrostatic potential of C50

Ab initio quantum chemical methods at the HF/6-31G* and MP2/6-31G* levels of theory were applied to the investigation of the relative stability of two fullerene isomers of C-50. Full geometry optimization of the systems was carried out and the electrostatic potential distributions were calculated. The effect of the electron correlation on the electrostatic potential distribution Of C-50 isomers was analyzed. The calculated results show that potential minima V-min(r) inside the sphere occur at the center of the sphere. The largest regions with the most negative MEP outside the sphere are localized in the neighborhood of pentagon-pentagon vertex fusions. They constitute most probably the active sites in chemical reactions. The present results might offer a more reasonable explanation for protonation and alkylation Of C-50 fullerene. (c) 2006 Elsevier B.V. All rights reserved.