Kinetic study of H+HF(v=3): Kinetic isotope effect and temperature dependence

Rates of HF(v=3) removal by H and D atoms were measured between 200 and 295 K in a laser-induced fluorescence–discharge flow–tube apparatus. The removal rates by H atoms were found to increase from 6.3×1013 cm3/mol s at 295 K to 10×1013 cm3/mol s at 200 K. The removal of HF(v=3) by D atoms is somewhat slower, but the removal rates have a similar negative temperature dependence. There are several mechanisms by which H atoms can remove HF(v=3), i.e., reaction to form H2+F or deactivation to HF(v=0, 1, or 2) with or without exchange of the F atom. The several possibilities are discussed and compared to theoretical calculations.