THERMOCHEMISTRY OF FULLERENE ANIONS IN THE GAS-PHASE

The gas-phase negative ion thermochemistry of fullerenes is the focus of this article. Fullerene anions are remarkably stable species and ha ve been observed in the solid state, in solution, and in the gas phase . Recent mass spectrometric observations of doubly charged anions of f ullerenes and some of their derivatives with electronegative addends p romise a new insight into the unique electronic properties of fulleren es. The gas-phase reactivity of fullerene anions and the energetics of electron-exchange reactions have been studied by the flowing afterglo w and Fourier Transform Mass Spectrometry methods. The application of Knudsen Cell Mass Spectrometry for studies of ion/molecular equilibria of fullerenes at elevated temperatures is discussed in detail. That m ethod has yielded electron affinities of the higher fullerenes and som e exo- and endohedral derivatives. The proposed method of the fulleren e fluoroderivatives generated in situ in a mass spectrometer has enabl ed determination of the C-F bond energies. Although simple in design a nd implementation, the method of Ion-Molecule Equilibria represents an effective and powerful tool for the thermochemical studies of such co mplex molecules as fullerene derivatives. (C) 1998 John Wiley & Sons, Inc.