Abstract
Two isostructural dinuclear lanthanide(III)/Schiff-base complexes [{Ce1.5Eu0.5(clapi)}2]·2CH3CN (1) and [{La1.5Eu0.5(clapi)}2]·2CH3CN (2) {H3clapi = 2-(5-chloride-2-hydroxyphenyl)-1,3-bis[4-(5-chloride-2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine} have been prepared by template procedure and characterized by elemental analyses, ICP, IR, and single-crystal X-ray diffraction analyses. Lanthanide ions Ce(III) and Eu(III) in 1, and La(III) and Eu(III) in 2 are disordered with occupancies 0.75 for Ce and 0.25 for Eu in 1; 0.75 for La and 0.25 for Eu in 2. In the compounds, each lanthanide is coordinated to four N and four O atoms from two clapi3− ligands, forming a distorted square antiprism. Two phenol oxygen atoms from the middle arms of the two heptadentate μ2-bridging ligands connect the two Ce(Eu) atoms in 1, and La(Eu) in 2. The solution of the two complexes in CH2Cl2 exhibits red fluorescence from Eu3+ ions at 77 K, very weak at room temperature.
Acknowledgements
Many thanks to Professor Xiaozeng You of Nanjing University, P. R. China, for his kindness and encouragement. The Project was sponsored by SRF for ROCS, SEM.