In 1975, the Priestley Medal was awarded to Henry Eyring by the American Chemical Society “to recognize distinguished services to chemistry,” the Society’s most prestigious award.

In November, 1934, he submitted to the Journal of Chemical Physics the paper entitled “The Activated Complex in Chemical Reactions” which showed that rates could be calculated using quantum mechanics for the potential surface, the theory of small vibrations to calculate the concentration and rate of crossing of the potential energy barrier. Whereas many people were enthusiastic about his breakthrough, others were skeptical.

The detailed description contained in this paper of the way chemical reactions proceed still dominates the formalism used for the description of reaction kinetics.