separability assumption

https://doi.org/10.1351/goldbook.S05611
This expression refers to the assumption, essential to conventional
transition-state theory
, that the energy of the system may be expressed as the sum of components associated with different
degrees of freedom
. In transition-state theory it is assumed that the energy of the motion of the system through the
dividing surface
of the
potential-energy (reaction) surface
is separable into various components. In many practical calculations it is assumed that the energy of the system is separable into electronic, vibrational, rotational and translational energy.
Source:
PAC, 1996, 68, 149. (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 186 [Terms] [Paper]