A determination of the stabilities and structures of F−(C6H6) and F−(C6F6) clusters

Abstract
The temperature dependence of the equilibria F+C6H6=F(C6H6) and F+C6F6=F(C6F6) was measured using a pulsed electron beam mass spectrometer. The −ΔH° values obtained are 15.3 and 27.5 kcal/mol, respectively. The measured enthalpy changes are reproduced by the ab initio MO calculations. While F(C6H6) involves a moderately strong hydrogen bond, the covalent bond is formed in the cluster F(C6F6) (i.e., tetrahedral structure).