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Updated: Jul 9, 2026
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Optical properties of a tetradentate bis(beta-diketonate) europium(III) complex
Biao Chen1, Yanhua Luo, Hao Liang
1Department of History of Science and Technology and Archaeometry, University of Science and Technology of China, Hefei, Anhui 230026, PR China. chenbiao@ustc.edu.cn
Abstract:
Eu2(BPOPB)3H2O, an europium complex chelated with bis(beta-diketone), was synthesized. Its properties have been investigated by absorption spectrum, emission spectrum and luminescence lifetime measurement. The complex displays strong red luminescence upon irradiation at the ligand band around 355 nm, which indicates that the bis-beta-diketonate ligand BPOPB is an efficient sensitizer. The Judd-Ofelt parameters obtained from the emission spectrum of Eu2(BPOPB)3H2O have been used to calculate the total spontaneous emission probabilities (A), the radiative lifetime (tau(rad)), the fluorescence branching ratio (beta) and the stimulated emission cross-sections (sigma). The luminescence lifetimes are determined to be 402 and 169 micros for Eu2(BPOPB)3H2O and Eu(DBM)3(H2O)2, respectively. The relationship between the structures of rare-earth complexes and luminescence lifetimes was analyzed. The radiative properties reveal that Eu2(BPOPB)3H2O is potential to be an efficient luminescent material.
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