pre-exponential factor, A

Also contains definition of: \(A\)-factor
Synonym: Arrhenius A factor
coefficient in front of the exponential factor expressing the empirical temperature dependence of the rate coefficient, k, on temperature, T,k = A exp^(-Ea/R.T), where Ea is the activation energy.
Green Book, 2nd ed., p. 56 (
PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 177 (