Photophysical properties of rhenium(I) tricarbonyl complexes containing alkyl- and aryl-substituted phenanthrolines as ligands
| Autor: | Lynne Wallace, D. P. Rillema |
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| Rok vydání: | 1993 |
| Předmět: | |
| Zdroj: | Inorganic Chemistry. 32:3836-3843 |
| ISSN: | 1520-510X 0020-1669 |
| DOI: | 10.1021/ic00070a012 |
| Popis: | A number of complexes of the type Re(L-L)(CO)[sub 3py][sup +] have been prepared, where L-L is 1,10-phenanthroline or a phenanthroline derivative containing methyl or phenyl groups and py is pyridine. All of the complexes are highly emissive at room temperature in solution or at 77 K in a glass, and the room-temperature luminescence data are consistent with emission from a [sup 3]MLCT state. The emission maximum ranges from 510 to 548 nm in CH[sub 2]Cl[sub 2], depending on L-L, and a linear relationship between [lambda][sub max] and the electrode potentials for oxidation and reduction is evident. Lifetimes in acetonitrile are of the order of several microseconds at room temperature (1.6-13 [mu]s), and emission quantum yields are very high (0.17-0.29). Results of photophysical measurements performed at low temperature indicate the presence of two unequilibrated emitting states, a [sup 3]MLCT and a [sup 3]LC (ligand-centered) state. Time-resolved spectra have established that the [sup 3]LC state is the longer-lived of the two and gives a structured spectrum similar to that of the uncoordinated ligand L-L. Both states show a dependence on the substitution pattern, and the contribution of each is uncoordinated ligand L-L. Both states shown a dependence on the substitution pattern, andmore » the contribution of each is determined by the particular L-L. Trends in the room-temperature data may also be accounted for by invoking a multistate model: however, the states are in thermal equilibrium under these conditions.« less |
| Databáze: | OpenAIRE |
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