Vibrational relaxation of highly excited diatomics. VII. DF(v=9–12) and HF(v=5–7)+HF(v=0), DF(v=0) in all combinations

Vibrational relaxation rate constants are measured for DF(v=9–12) and HF(v=5–7) by ground state HF and DF using the fast-flow infrared chemiluminescence technique. The 14 rate constants range from (1.4 to 5.5)×10−10 cm3 s−1, i.e., probabilities per gas-kinetic (Lennard–Jones) collision from 0.47 to 1.72. The rate constants are independent of the magnitude or sign of the vibrational (V→V) energy defect which indicates that these are V→R,T processes. They are slightly faster for HF than for DF quencher. These results are discussed in the context of theoretical trajectory calculations and comparisons with other highly excited diatomics as well as other quenchers.