TICT states and beyond: Reaction dimensionality and application to photosynthesis

Abstract

Twisted intramolecular charge transfer (TICT) states are reviewed, and their relation to the more general model of biradicaloid charge transfer states (BCT) is shown. Examples include donor-acceptor-stilbenes where twisting can occur around single and/or double bonds. Another kind of multidimensionality is encountered in systems where different donor goups are linked to one acceptor. This is exemplified with a series of benzopyrylium dyes. Finally, symmetric biaryl systems are shown to be molecular models for understanding some of the intriguing questions of photosynthesis (orthogonality of the chromophores, inequivalence of L and M electron transfer paths). © 1992 Indian Academy of Sciences.