The reaction SF+5 + H2S at near thermal energies: competition between association and binary reactions

Abstract The reaction between SF + 5 has been investigated in the energy from 0.052 to 1.7 eV, KE cm , using a selected ion flow drift tube (SIFDT) operating with helium buffer gas. At low energies a slow binary reactions channel into SF 4 HS + occurs in parallel with a fast association reaction. Both rate coefficients decline from 3×10 −11 cm 3 s −1 and 3×10 −27 cm 6 s −1 respectively at 0.052 eV to −12 cm 3 s −1 and −28 cm 6 s −1 respectively at 0.3 eV, KE cm . Above 0.3 eV the endoergic charge transfer channel becomes dominant, the rate coefficient increasing to 9×10 −12 cm 3 s −1 at 1.7 eV, KE cm . SF + 5 ·H 2 S was found to react fast with H 2 S, the rate coefficient being 1.4×10 −9 cm 3 s −1 .