Luminescence of the films of europium (III) with thenoyltrifluoroacetonateand macrocyclics

We discuss the syntheses, properties and the luminescence of the complexes, Eu(TTA)(3) . 2L . H2O, where TTA = thenoyltrifluoroacetonate, L=15C5 (1,4, 7,10-tetraoxa-13-azacyclopentadecane,13-phenyl) and 18C6 (2,3,11,12-dicyclo hexano-1,4,7,10, 13,16-hexaoxacyclooctadecane). The film complexes with 15C 5 and 18C6 ligands contain only one water molecule. The Omega(lambda) exper imental intensity parameters (lambda=2 and 4) and the ratio between the int ensities of the D-5(0) --> F-7(0) and D-5(0) --> F-7(2) transitions (R-02) were obtained for the compounds Eu(TTA)(3) . 2(15C5) . H2O (Omega(2) = 39.5 x 10(-20) cm(2), Omega(4) = 8.9 x 10(-20) cm(2) and R-02 = 0.0087) and Eu( TTA)(3) . 2(18C6) . H2O (Omega(2) = 39.3 x 10(-20) cm(2), Omega(4) = 5.8 x 10(-20) cm(2) and R-02 = 0.0098). The macrocyclic compounds, powder form, w ere also measured. The luminescence spectra of the Eu(TTA)(3) . 2L . H2O fi lms give the largest Omega(2) intensity parameter, due to the hypersensitiv e D-5(0) --> F-7(2) transition and indicating that the rare earth ion is in a polarizable chemical environment. The lifetimes of the macrocyclics comp lexes in the powder and film were measured. (C) 1999 Elsevier Science B.V. All rights reserved.