711 Luminescence Properties of Organometallic Complexes ALISTAIR J. LEES oepartmmt of zyxwvutsrqpo ~ h y , (Inlversny Center zyxwvuts ai Binghamion. zyxwvutsrq Sbie unhws#y of New YaX, Bhylhamton, New YaX 13901 Rec&d "tu 17. 1986 (Revised hfnnurcnpt Received March 19. 1987) Contents 1. Introduction A. Scope of Thls Review E. Types of Excked States In Organometallic Complexes 1. Ligand Field Excked States 2. Metal to Ligand Charge-Transfer 3. Ligand to Metal Charge-Transfer 4. Metal to Solvent Charge-Transfer 5. Metal to Metal ChargeTransfer Excked 6. lntrallgand ExcRed States Excited States Excited States Excited States States 11. Photoluminescence A. Metal Carbonyls 1. Vanadium, Niobium. and Tantalum 2. Chromium, Moiybdenum, and Tungsten 3. Manganese and Rhenium Complexes 4. Iron, Ruthenium. and Osmium 5. Rhodium and Iridium Complexes B. Metallocenes 1. Ferrocene 2. Ruthenocene C. Metal IsocyanMes 1. Chromium, Molybdenum. and Tungsten 2. Rhodium Complexes 1. Rhodium and Iridium Complexes 2. Platinum Complexes E. Ortho-Metalated Complexes 1. Ruthenium Complexes 2. Rhodium and Iridium Complexes 3. Palladium and Platinum Complexes Complexes Complexes Complexes Complexes D. Alkenes F. Dinlhcgen Complexes 111. Chemiluminescence IV. Electrogenerated Chemiluminescence V. Closing Remarks VI. Acknowledgments VII. References I . Introductbn A. Scope of Thls Revlew 711 711 712 712 712 712 712 712 712 712 712 713 714 722 730 731 731 73 1 732 732 733 733 733 733 735 735 735 735 737 738 738 739 740 740 740 Most investigations in inorganic photochemistry have been concerned with classical coordination compounds, and these have lead to a good understanding of the 0009-2e~5/87/0787-0711$08.50/0 r Allstak J. Lees was born In Preston. Engiand. in 1955 and raid In me far-north of Scotland. He received his Ph.D. Wree from z the University of Newcastleupon-Tym, In 1979 under the direction of Brian P. Shaughan and was then a Postdoctoral Fellow from 1979 to 1981 at the University of Smithern California with Arthur W. Adamxwr. In 1981 he joined the facuity at the State University of New York In Binghamton where he Is currently an Associate Professor. His research interests are in the synthesis and spec- troscopy of inorganic and organometallic complexes whh an em phasis on photochemical and catalytic processes. He is manied and has two children. excited-state proceeses in these complexes. This field has developed rapidly over the past 30 years, and there already exist a number of review papers that have helped capture the vast expansion of its literature.'-" Although the photoreactivity of metal carbonyls has been studied extensively and has been the subject of several reviews,'J*-*' the photochemistry of other types of organometallic complexes remains much less un- derstood. Only recently have critical summaries ap- peared on this topic!.** This review paper is concemed with the luminescence properties of organometallic complexes and in particular emphasizes how studies of this nature have been used to gain valuable insight on the excited-state processes of these molecules. An indication that this is a rapidly growing area of interest is demonstrated by the fre- quency of literature citations. There are very few re- search papers in this area prior to the mid 19709, and a significant fraction of the early reports on lumines- cence represent rather isolated examples rather than structured research investigations. It is the primary purpose of this review to link together these reports and thus provide a foundation for future studies in this area. An attempt has been made to be definitive, and the literature has been extensively searched from 1968 to 1986 via both book and online searches of Chemical 0 1987 American Chemical Society