PHOTOCHEMISTRY AND PHOTOCATALYSIS OF RHENIUM(I) DIIMINE COMPLEXES

Rhenium(I) diimine carbonyl complexes have been well investigated because of their functionalities, such as the intense emission properties, capabilities as a building block for multinuclear complexes, and photocatalytic activities. This chapter describes the following three topics of the rhenium complexes including recent reported works: photophysics, photochemical reactions, and photocatalyses. After Section I, the photophysical processes of the rhenium complexes are briefly summarized: the electronic structures, the photophysical relaxation processes, and the effects of intramolecular weak interaction between ligands on the photophysical properties. The next section about photochemical reactions includes ligand substitution, homolysis, and reactions of the ligand on the rhenium complexes. This section also includes synthesis of emissive multinuclear rhenium(I) complexes using the photochemical ligand substitution. The last section describes unique and high photocatalytic activities of the rhenium(I) diimine carbonyl complexes, especially for CO2 reduction. The photocatalyses of mononuclear rhenium complexes, multicomponent systems, supramolecular systems with a Ru(II) complex as a photosensitizer, and a rhenium complex with periodic mesoporous organosilica as a light-harvesting system.