Reactions of Molecules in Defined Vibrational States VII. Absolute Rate Determination for the Reaction of D‐Atoms with Vibrationally Excited H₂‐Molecules

Using a discharge‐flow reactor and energy transfer from laser excited HF molecules we have directly measured, that the rate of the reaction D + H 2 increases by a factor of 4.10 4 at 298 K after single quantum vibrational excitation of the H 2 molecule. Substantially smaller rate enhancements are predicted by presently available quasiclassical and quantum calculations using the most accurate ab initio potential energy surface.