Intermolecular energy transfer between Tb(thd)3 and Eu(thd)3 complexes in solution
Brittain, Harry G.; Richardson, Frederick S.
Журнал:
Journal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics
Дата:
1977
Аннотация:
Intermolecular energy transfer between Tb(thd)3 and Eu(thd)3 chelates (thd = 2,2,6,6-tetra-methyl-3,5-heptanedione) in a variety of solvents at room temperature is studied by both emission life-time and steady-state emission intensity techniques. Thirteen different solvents were examined, ranging from strongly coordinating dimethylsulphoxide (dmso) and dimethylformamide (dmf) to very weakly coordinating carbon tetrachloride (CCl4) and chloroform (CHCl3). Quenching of Tb(thd)3 emission by Eu(thd)3 was observed in all solvents except dmso, dmf and pyridine. Comparison of Sternâ Volmer quenching constants obtained from lifetime measurements (K Ï sv) versus intensity measurements (K Ï sv) indicates a dominant dynamical quenching mechanism; no evidence is found for the formation of (mixed) dimeric species involving the Tb(thd)3 and Eu(thd)3 chelate systems. Bimolecular quenching rate constants, Sternâ Volmer quenching constants, and emission lifetime data are reported for each of the solvents in which Tb(thd)3 emission and Tb(thd)3â Eu(thd)3 energy transfer were observed.
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