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 ( − E a / R T ), where E a is the activation energy.
Source:
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