Divalent Europium Complexes with Phenochalcogenato Ligands: Syntheses, Crystal Structures, and Luminescence Properties
Year: 2025
Type: article
Abstract: Divalent europium complexes have attracted significant attention in various fields due to the unique electronic configuration of the Eu(II) ion. Given the high sensitivity of the 5d → 4f emission of Eu(II) ions to the ligand field, it is crucial to explore the relationship between ligands and this emission in Eu(II) complexes. However, the heavy-atom effects on the 5d → 4f emission of Eu(II) complexes coordinated with non-metal elements in the same group remain unclear. In this study, five mononuclear Eu(II)-chalcogenide complexes, Eu[H3B·EPh-κE,H,H]2(DME)2 (E = S for 1 and Se for 2; DME = 1,2-Dimethoxyethane) and Eu[EPh]2(18-C-6) (E = S for 3, Se for 4, and Te for 5; 18-C-6 = 1,4,7,10,13,16-Hexaoxacyclooctadecane), were synthesized via reduction of diphenyl disulfide chalcogenide analogs with Eu(BH4)2(THF)2 or NaH. The structures of these complexes were investigated by single-crystal X-ray diffraction, and their properties were characterized by thermogravimetric analysis and photophysical property tests. Complexes 1 and 2 are isomorphous and show similar yellowish-green luminescence, while complexes 3–5 have similar structures but crystallize in different space groups with bluish-green luminescence. This research reveals the influence of chalcogenide ligands on the 5d → 4f emission of Eu(II) complexes, providing a theoretical basis and new research ideas for the application of Eu(II) complexes in various fields, including luminescent materials, cryogenic refrigerants, and magnetic materials.
Source: Inorganics
Institution: Southern University of Science and Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,654
OpenAlex ID: W4417426517