Quantum effects on ion–dipole capture rate coefficients

Abstract

A recent theoretical study of the ion–dipole capture process using classical variational and effective potential methods is extended to the quantum regime. Capture rate coefficients are calculated for the ion–dipole potential energy surface utilizing a model where the vibrations are frozen, the rotations are quantized and the translational motion is classical. Results from a simple adiabatic capture theory, variational transition state theory, and an effective potential method are presented and compared with the corresponding classical rate coefficients and with results from classical trajectory calculations for H+3 ions colliding with HCl, HCN, and CS. Comparison is also made with other theoretical and experimental results.