Rotational energy transfer in HF

Abstract

A rotational nonequilibrium model has been developed to simulate the infrared double-resonance experimental technique designed to study rotational relaxation of HF gas in the v=1 and higher vibrational states. State-to-state rate coefficients for this rotation-to-translation relaxation model have been obtained from a surprisal analysis and are found to scale as an inverse power of the rotational energy transferred. Phenomenological rates for the rotational energy transfer in the v=1 state for J=0 to J=7 with Δ J =+1, +2, +3, and +4 are found to be in excellent agreement with the reported phenomenological rates from available experiments for both the v=1 and v=2 states. It appears, therefore, that the state-to-state rate coefficients for rotational relaxation of HF are insensitive to the v state. Angular momentum statistics corresponding to conservation of mj are found to give better fits to the data than those with mj assumed to be completely randomized.