Luminescence investigation of the Sm(III)-b-diketonates with sulfoxides, phosphine oxides and amides ligands.

• Autor(a) principal: Brito, Hermi Felinto de
• Data de Publicação: 2002
• Outros Autores: Malta, Oscar Manoel Loureiro, Felinto, Maria Claudia França da Cunha, Teotonio, Ercules Epaminondas de Sousa, Menezes, Jorge Fernando Silva de, Silva, C. F. B., Tomiyama, C. S., Carvalho, Carlos Alberto Alves de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFOP
• Texto Completo: http://www.repositorio.ufop.br/handle/123456789/4866; https://doi.org/10.1016/S0925-8388(02)00372-9
• topic: Samarium; Luminescence; Thenoyltrifluoroacetonate; Sulfoxides and amides

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) dehydrated 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 31 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 andh ) 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.