## Wikipedia - Pre-exponential factor pre-exponential factor, $$A$$

Also contains definition of: $$A$$-factor
Synonym: Arrhenius A factor
https://doi.org/10.1351/goldbook.P04811
@C01124@ in front of the exponential factor expressing the empirical temperature dependence of the @R05137@, $$k$$, on temperature, $$T$$,$$k=A\ \exp (- E_{\text{a}}/R\ T)$$, where $$E_{\text{a}}$$ is the @A00093@ energy.
Sources:
Green Book, 2nd ed., p. 56 [Terms] [Book]
PAC, 1996, 68, 149. (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 177 [Terms] [Paper]