The luminescence properties of heteroleptic [OsCl(CO)(N∩N)(P∩P)](+) complexes - radiative and non-radiative deactivation of the excited (3)*MLCT state.
The luminescence properties of the heteroleptic [OsCl(CO)(N∩N)(P∩P)](+) complexes with bidentate phosphine P∩P and diimine N∩N ligands have been studied in acetonitrile solutions at room temperature and in methanol/ethanol (1 : 1) glasses at 77 K. At room temperature the investigated complexes feature strong (with the quantum yields ϕem from 0.17 up to 0.64), long-lived (with lifetimes τem in the range of 1.5-44.2 μs) (3)*MLCT emission. Analysis of (3)*MLCT emission band shapes leads to the quantities relevant for the radiative electron transfer (between the Os(2+) central ion and the N∩N ligand) in the Marcus inverted region. It is also demonstrated that radiative kr and non-radiative knr decay rate constants of the excited (3)*MLCT states can be interpreted within the Mulliken-Hush formalism. Especially values of knr rate constants can be predicted using the parameters available from the analysis of the radiative (1)*MLCT ← S0 and (3)*MLCT → S0 charge transfer processes.
Institute of Chemistry, Faculty of Sciences, Siedlce University of Natural Sciences and Humanities, 3 Maja 54, 08-110 Siedlce, Poland. andrzej.kapturkiewicz@uph.edu.pl.
Anna
A
Kamecka
Andrzej
A
Kapturkiewicz