Study of kinetics of luminescence and triplet-triplet absorption of a mixture of europium and gadolinium chelate complexes in finely porous glass

摘要

Spectral and kinetic characteristics of luminescence of the Eu~(3+) complex EuTTA_3Phen (where TTA is thenoyltrifluoroacetone and Phen is 1,10-phenanthroline) and the triplet state ~3TTA of the nonluminescent complex GdTTA_3 Phen, as well as mixtures of these complexes, have been studied in a CH_2Cl_2 solution, in finely porous glass (PG) filled with the solution, in a CH_2Cl_ 2 monolayer on the PG surface, and in the adsorbed state on the dry PG surface. The yields of Eu3+ luminescence and ~3TTA for mixtures of the complexes in a solution, including the solution located in PG, correspond to those expected from the portion of the absorbed light. However, in the monolayer and on a dry PG surface, the luminescence yield observed is substantially higher and the ~3TTA yield is lower than those expected, which is due to static energy transfer from the triplet states of TTA in the complex with Gd~(3+) to TTA in the complex with Eu~(3+) in mixed clusters of the complexes on the surface.