Synthesis, structure and properties of a tetranuclear europium(III) complex based on 9,9-dimethylfluorene-2,7-diphosphonic acid
                                
                                    
                                        作者:Liang Li、Ao Li、Lin Song、Zi-Hao Wang、Xin-Hui Zhou、Tao Yang、Wei Huang                                    
                                    
                                        DOI:10.1016/j.molstruc.2014.03.015
                                    
                                    
                                        日期:2014.6
                                    
                                    One tetranuclear europium(III) phosphonate complex [Eu-2(H4MFDP)(H3MFDP)(4)(H2MFDP)(H2O)(4)]center dot 13.5H(2)O (EuMFDP), has been prepared by reactions of the new ligand 9,9-dimethylfluorene-2,7-diphosphonic acid (H4MFDP) with europium(III) nitrates. The crystal structure of complex EuMFDP has been determined using single-crystal X-ray diffraction. It features a strip-like tetranuclear structure, in which four ligands and four Eu(III) ions constitute the core. Interestingly, the four ligands in the core possess paddle-like arrangement. Although the free ligand H4MFDP exhibits the emission centered at 333 nm and 438 nm upon excitation at 310 nm, complex EuMFDP shows only very weak characteristic emission of Eu(III) ions, probably due to the strong quenching effect of OH vibration. The thermal property of EuMFDP has also been studied. Crown Copyright (C) 2014 Published by Elsevier B.V. All rights reserved.