Photoaquation Reactions of Chromium(III) Polypyridine Complexes Induced by Sequential Biphotonic Irradiations.

The long-lived, low-lying doublet states of Cr(III) polypyridine complexes have been generated and irradiated by using sequential biphotonic techniques. The detection of products and the time-resolved spectroscopy of the processes have shown that biphotonic irradiation induces a ligand photolabilization independent of acid concentration. Such a reaction cannot be associated with the photolabilization induced in monophotonic irradiations with low light intensities and has been related to processes initiated in upper excited states. 17 refs., 3 figs., 1 tab.