title: Reflection on medium effects on photochemical reactivity.
abstract: In reexamining medium effects on photochemical reactions, we have emphasized those on unequilibrated excited species such as the Franck-Condon species. Despite recent advances in femtochemistry, such a discussion in molecular photochemistry is uncommon, and the problem remains challenging on account of the extremely short-lived excited species. However, in such cases, a small perturbation resulting from, for example, weak guest-host interactions could turn into a determining factor in dictating the course of a photochemical channel of deactivation. Examples of medium-directed diabatic processes have been examined with this idea in mind. A modified view on rhodopsin photoisomerization is presented along with the consideration that confinement does not necessarily lead to inhibition of reactions of the trapped substrate.
authors.affiliation: Department of Chemistry, University of Hawaii, 2545 The Mall, Honolulu, Hawaii 96822, USA. rliu@gold.chem.hawaii.edu
authors.forename: Robert S H
authors.initials: RS
authors.lastname: Liu
authors.forename: George S
authors.initials: GS
authors.lastname: Hammond
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D007536:Isomerism; D008958:Models, Molecular; D015394:Molecular Structure; D010777:Photochemistry; D020283:Photoreceptors, Microbial / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012243:Rhodopsin / Q000737:chemistry / Q000378:metabolism; D012996:Solutions
chemical_list: D001426:Bacterial Proteins; D020283:Photoreceptors, Microbial; D012996:Solutions; C050162:photoactive yellow protein, Bacteria; D012243:Rhodopsin