Mechanisms of Energy Transfer in Hydrogen Fluoride Systems.

Abstract

Rate coefficients are calculated for the energy‐transfer processes that ocuur when HF(v1,J1) molecules collide with HF(v2, J2) molecules. Three‐dimensional classical trajectories of the collision dynamics of these energy‐transfer processes were calculated by means of a potential energy surface, which consists of a London–Eyring–Polanyi–Sato (LEPS) potential function for the short‐range interactions and a partial‐point‐charge, dipole–dipole function for long‐range interactions. This energy surface was used to predict an equilibrium geometry of the HF dimer. From the trajectory calculations it was predicted that the v→v energy‐transfer processes occur by means of Δv=±1 transitions and that the rate coefficients for the processes HF(v)+HF(v=0) →HF(v−1)+HF(v=1) decrease with increasing vibrational quantum number v. A calculation of the v→v rate for the reaction HF(v=1)+HF(v=1) →HF(v=0)+HF(v=2) indicates a value of 1.2×1013 cm3 mol−1 s−1 at 300 K. This process corresponds to near‐resonant vibration‐to‐vibratio...