In this paper we report on a photoluminescent investigation of complexes involving Sm-b-diketonates with sulfoxides, phosphine oxides and amides ligands. In the synthesis of the coordination compounds we used samarium tris(thenoyltrifluoroacetonate) dihydrated precursor with the following ligands (L): DBSO and PTSO sulfoxides; TPPO phosphine oxide and (PHA) N-phenylacetamide. They have 31 31 shown high orange luminescence characteristic of the Sm ion. The emission spectra of the Sm-complexes present narrow bands 4 6 4 6 arising from the G → H (J55 / 2, 7 / 2, 9 / 2, 11 / 2) transitions with the hypersensitive G → H transition as a prominent group. It 5 / 2 J 5 / 2 9 / 2 4 3 1 is observed an efficient intramolecular energy transfer from the triplet state (T) of the ligands to the emitting G state of the Sm ion. 5 / 2 The experimental intensity parameters (h and h) for the Sm and Eu complexes have been determined and compared. The lifetimes (t) Sm Eu 4 of the emitting level G of the Sm-complexes are approximately 10 times higher than in the precursor compound [Sm(TTA) ?(H O) ] 5 / 2 3 2 2 indicating that radiative processes are operative in all the compounds due to the absence of multiphonon relaxation by coupling with the OH oscillators.

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We discuss the syntheses, properties and the luminescence of the complexes, Eu(TTA) 3 á 2L á H 2 O, where TTA thenoyltri¯uoroacetonate, L 15C5 (1,4,7,10-tetraoxa-13-azacyclopentadecane,13-phenyl) and 18C6 (2,3,11,12-dicyclohexano-1,4,7,10,13,16-hexaoxacyclooctadecane). The ®lm complexes with 15C5 and 18C6 ligands contain only one water molecule. The X k experimental intensity parameters (k 2 and 4) and the ratio between the intensities of the 5 D 0 ® 7 F 0 and 5 D 0 ® 7 F 2 transitions (R 02 ) were obtained for the compounds Eu(TTA) 3 á 2(15C5) á H 2 O (X 2 39.5´10 À20 cm 2 , X 4 8.9´10 À20 cm 2 and R 02 0.0087) and Eu(TTA) 3 á 2(18C6) á H 2 O (X 2 39.3´10 À20 cm 2 , X 4 5.8´10 À20 cm 2 and R 02 0.0098). The macrocyclic compounds, powder form, were also measured. The luminescence spectra of the Eu(TTA) 3 á 2L á H 2 O ®lms give the largest X 2 intensity parameter, due to the hypersensitive 5 D 0 ® 7 F 2 transition and indicating that the rare earth ion is in a polarizable chemical environment. The lifetimes of the macrocyclics complexes in the powder and ®lm were measured.