Negative ion chemistry and the electron affinity of SF6

An extensive study of negative ion–molecule chemistry involving SF6 and SF−6 utilizing the room temperature flowing afterglow technique is reported. Based on a series of limit determinations, the recommended value of E.A.(SF6) is 1.0±0.2 eV. The discrepancy between this value and several previous determinations of E.A. (SF6) is discussed in terms of systematic experimental conditions and the formation of an excited state of SF−6. A large number of reaction rate coefficients as well as qualitative observations of reaction mechanisms are presented.