On the chromism of polyenes

At a constant temperature, the change in energy of the 1Ag -> 1Bu electronic transition of a polyene with the solvent depends on solvent polarizability. For the same solvent and polyene, as the temperature varies, however, the energy of the 1Ag -> 1Bu electronic transition not only depends on polarizability but also quite strongly on alterations of the chemical structure of the polyene. (C) 2008 Elsevier B.V. All rights reserved.