Electronic structures of the icosahedral C60H60 and C60F60 molecules

Abstract Electronic structures of the icosahedral C 60 H 60 hydrocarbon and its perfluoro analog, C 60 F 60 , are examined at the HF/4-31G and HF/6-31G** levels. The calculated CC bond lengths are as large as 1.57 A in C 60 H 60 and 1.63 A in C 60 F 60 . The bond lengthening is attributed to the HH and FF steric interactions rather than to rehybridization effects. Topological analysis of the electron densities reveals the presence of curve CC bond paths. In addition, FF bond paths are found in C 60 F 60 indicating strong non-bonded interaction between the fluorine atoms. The same conclusion is reached from the calculated energy of the isodesmic transfluorination reaction involving the C 2 H 6 , C 2 F 6 , C 60 H 60 , and C 60 F 60 molecules.

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