Department of Chemistry

Department of Chemistry University of Oxford

Isotopic substitution has long been used to understand the detailed mechanisms of chemical reactions; normally the substitution of hydrogen by deuterium leads to a slower reaction.  New research by the Heazlewood group, published in Nature Communications, observed an inverse Kinetic Isotope Effect (KIE) in the charge transfer reaction of Xe+ ions with isotopologues of ammonia; deuterated ammonia was found to react more than three times faster than hydrogenated ammonia.  The higher reactivity of deuterated ammonia is attributed to the greater density of states of the deuterated reaction complex compared to the hydrogenated system, observations that could provide valuable insight into possible mechanisms contributing to deuterium fractionation in the interstellar medium.