Interaction between electronic and vibrational motions in a molecular entity.
See: Jahn–Teller effect, Renner–Teller effect
Source:
PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2283 (https://doi.org/10.1351/pac199668122223)