Influence of electron-donor properties of ligands on temperature quenching of luminescence in europium tris-β-diketonates

Influence of donor-acceptor activity of the organic ligand terminal groups on the effectiveness of nonradiating dissipation of electron energy of the Eu3+ excitation on the environment ligands in the series of europium tris-β-diketonates. Eu(L)3Phen, where L-β-diketones: acetylacetone (AA), benzeneacetone, dibenzoylmethane (DBM), dipivaloylmethane, thenooyltrifluoroacetone, hexafluoroacetylacetone, trifluoroacetylacetone, Phen. - 1.10-phenanthroline. The values of the activation energies, which monotonically decrease at transition from alkyl and aryl substituents to fluorated β-diketonates are obtained from the curves of temperature quenching (100-300 K). The correlation between the activation energy and ''σ'' Taft constant is obtained