Crystal Structure and Highly Luminescent Properties Studies of Bis-β-diketonate Lanthanide Complexes

• Published in: Inorganic chemistry Vol. 52; no. 9; pp. 5013 - 5022
• Main Authors: Shi, Jing, Hou, Yanjun, Chu, Wenyi, Shi, Xiaohong, Gu, Huiquan, Wang, Bilin, Sun, Zhizhong
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 06.05.2013
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic302726z

A new bis(β-diketonate), 1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenyl (BTP), which contains a trifluorinated alkyl group, has been prepared for the synthesis of two series of dinuclear lanthanide complexes with the general formula Ln2(BTP)3L2 [Ln3+ = Eu3+, L = DME(1), bpy(2), and phen(3); Ln3+ = Sm3+, L = DME(4), bpy(5), and phen(6); DME = ethylene glycol dimethyl ether, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline]. The crystal structure of the free ligand has been determined and shows a twisted arrangement of the two binding sites around the 1,3-phenylene spacer. X-ray crystallographic analysis reveals that complexes 1, 2, 4, and 5 are triple-stranded dinuclear structures formed by three bis-bidentate ligands with two lanthanide ions. The room-temperature photoluminescence (PL) spectra of complexes 1–6 show that this bis-β-diketonate can effectively sensitize rare earths (Sm3+ and Eu3+) and produce characteristic emissions of the corresponding Eu3+ and Sm3+ ions. In addition, two bidentate nitrogen ancillary ligands, 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), have been employed to enhance the luminescence quantum yields and lifetimes of both series of Eu3+ and Sm3+ complexes.