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 C50. 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 C50 isomers was analyzed. The calculated results show that potential minima Vmin(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 C50 fullerene.