This term is applied to a kinetic study in which there is emphasis on the behaviour of the system at the molecular level.
See: macroscopic kinetics
Source:
PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 175 (https://doi.org/10.1351/pac199668010149)