Ta. Claxton et al., BONDING AND DELOCALIZATION IN C-60 VIA TOPOGRAPHICAL ANALYSIS OF THE ELECTROSTATIC POTENTIAL AND ELECTRON-DENSITY, Journal of the Chemical Society, Chemical Communications, (6), 1994, pp. 731-732
Analysis of the ab initio electron density distribution of C60 show th
at all exo bonds to the five-membered rings have partial double-bond c
haracter with all molecular electrostatic potential minima located out
side the molecular cage.