Reactions with Fluorocarbons CF4 and

The reactions of 0+ and Oj with CF4 and C2Fg have also been examined (Fisher and Armentrout, 1991c). In both systems, the predominant ions formed correspond to dissociative charge-transfer reactions, with small amounts of FCO+ and F2CO+ being formed. As for the rare gas system, the thresholds and shapes of the 

Our study of the reactions of rare gas ions with CF4 made it clear that the heat of formation of CF was not well established. Because of the severe Jahn-Teller distortion upon ionization, measured photoionization thresholds for formation of 

CF from CF4 are generally too high, and even photoelectron-photoion coincidence experiments provide only upper limits (Brehm et al., 1974 Powis, 1980). We therefore performed a series of experiments designed to determine this heat of formation (Fisher and Armentrout, 1990d). In contrast to a literature report (Babcock and Streit, 1981), we demonstrated that there can be no fluoride transfer equilibrixrm between CFj and SF at thermal energies by examining both the forward and reverse reactions (21)  

This conclusion agrees with that of Sieck and Ausloos (1990). In our work, we measured the threshold for formation of CF from the reaction of ground state Kr ( P3/2) with CF4 to establish This value agreed well with a less 

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