Abstract
The vibrational relaxation rate constant kl→0 (T) over T?500 K was computed for para‐H2 in He from fully converged CC cross sections. While the calculated rate constant is much too large, it displays a hump around T=100 K, presenting, for the first time, a plausible elucidation of the humps in the experimental results of Audibert et al. Analyses of the present results and that of Raczkowski et al. seem to indicate that the overestimation by the present work is perhaps mainly due to the nature of the intermolecular potential and that a close‐coupling scheme and an accurate potential surface should reproduce the experimental results.