Reaction @[email protected] (thermal or photoinduced) between neutral molecular or atomic entities in which long-range @[email protected] is followed by a considerable reduction of the distance between donor and acceptor sites as a result of the electrostatic attraction in the @[email protected] created.
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2245 [Terms] [Paper]