Excited state properties of organometallic compounds of rhenium in high and low oxidation states

Organometallic compounds of rhenium occur in high and low oxidation states. These complexes are characterized by a variety of excited states including ligand held (LF), ligand-to-metal charge transfer (LMCT), metal-to-ligand charge transfer (MLCT), ligand-to-ligand charge transfer (LLCT), metal-to-m etal charge transfer (MMCT), and intraligand (IL) excited states. The natur e of the lowest-energy excited state can be tuned by the choice of appropri ate ligands and metal oxidation states. This diversity is illustrated by se lected examples of organometallics of Re(VII) and Re(I). Our account emphas izes spectral (absorption and emission) as well as photochemical properties . (C) 2000 Elsevier Science S.A. All rights reserved.