Your browser doesn't support javascript.
loading
Unusually Large Ligand Field Splitting in Anionic Europium(III) Complexes Induced by a Small Imidazolic Counterion.
Blois, Lucca; Costa, Israel F; Honorato, João; V Sanches de Araújo, Adalberto; Ando, Rômulo A; Carneiro Neto, Albano N; Suta, Markus; Malta, Oscar L; Brito, Hermi F.
Afiliación
  • Blois L; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
  • Costa IF; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
  • Honorato J; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
  • V Sanches de Araújo A; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
  • Ando RA; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
  • Carneiro Neto AN; Physics Department and CICECO─Aveiro Institute of Materials, University of Aveiro, Aveiro 3810-193, Portugal.
  • Suta M; Inorganic Photoactive Materials, Institute of Inorganic Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
  • Malta OL; Department of Fundamental Chemistry, Federal University of Pernambuco, Recife 50740-560, Brazil.
  • Brito HF; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, Brazil.
Inorg Chem ; 63(36): 16861-16871, 2024 Sep 09.
Article en En | MEDLINE | ID: mdl-39197034
ABSTRACT
Luminescent trivalent lanthanide (Ln3+) complexes are compounds of technological interest due to their unique photophysical properties, particularly anionic tetrakis complexes, given their higher stability and emission quantum yields. However, structural studies on the cation-anion interaction in these complexes and the relation of such to luminescence are still lacking. Herein, the cation-anion interactions in two luminescent anionic tetrakis(2-thenoyltrifluoroacetonato)europate(III) complexes with alkylimidazolium cations, specifically 1-ethyl-3-methylimidazolium and 1-butyl-3-methylimidazolium are investigated. The Eu3+ complexes were synthesized and characterized by elemental analysis, mass spectrometry, and single-crystal X-ray crystallography, and their luminescence spectra were recorded at 77 K. Quantum chemical calculations were also performed. X-ray crystallography revealed hydrogen bonds between the enolate ligands and imidazolium ring hydrogens. The 1-butyl-3-methylimidazolium complex had two crystallographic Eu3+ sites, also confirmed by luminescence spectroscopy. The 1-ethyl-3-methylimidazolium complex exhibited an unusual 300 cm-1 splitting in the 5D0 → 7F1 transition, as reproduced by ligand field calculations, suggesting a stronger hydrogen bonding due to the smaller substituent. We hypothesize that this strong bonding likely causes angular distortions, resulting in high ligand field splittings.

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Idioma: En Revista: Inorg Chem Año: 2024 Tipo del documento: Article País de afiliación: Brasil Pais de publicación: Estados Unidos

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Idioma: En Revista: Inorg Chem Año: 2024 Tipo del documento: Article País de afiliación: Brasil Pais de publicación: Estados Unidos