Direct observation of HSF+6 and the bracketing of the SF6 proton affinity at 5 K

Abstract

Formation of stable HSF+6 via proton transfer at 5 K is reported. A bracketing study determines the 298 K proton affinity of SF6 to be 139.4±2.0 kcal mol−1 in agreement with the only previously reported observation of HSF+6. In addition, an upper bound to the appearance energy for SF+5 of 321.9 kcal mol−1 is determined.