Rate constants for the thermal energy reactions of He+, He(21S), and He(23S) with HCl and HBr

The rate constants for the reactions of He+, He(21S), and He(23S) with HCl and HBr are reported. The charge-transfer reactions are dissociative and the rate constants lie between the Langevin and locked dipole rates. The Penning ionization rate constants are also large. The ratio of singlet-to-triplet cross sections is 2.3.