Coefficients of quantum numbers in the rotational
term
expression and inversely proportional to the
principal moments of inertia.
Symbols:

,

,

.

(dimension wavenumber),

(dimension frequency) where

is the
Planck constant and

the speed of light in vacuum.
Source:
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.