The first 3-D La super(III)-Sr super(II) heterometallic complex: Synthesis, structure and luminescent properties

The first 3-D La super(III)-Sr super(II) heterometallic complex, namely [La sub(2)Sr(pda) sub(4)(H sub(2)O) sub(4)] sub(n).6nH sub(2)O (1, H sub(2)pda = pyridine-2,6-dicarboxylic acid), has been successfully synthesized under solvothermal conditions. Single crystal X-ray diffraction analysis reveals that complex 1 features a 3-D porous framework and displays a new topology. The crystal structure can be simplified to a 4,6-connected 3-D network with Schlaefli symbol of {3 super(4).4 super(2).8 super(8).9} sub(2){3 super(4).4 super(2)}. The crystals also have been characterized by X-ray powder diffraction, elemental analysis, thermal analysis, and IR spectroscopy. The infrared spectral analysis indicates that complex 1 is a carboxylate coordinated compound, several water molecules exist in the compound. The thermal study shows that there are ten water molecules in the crystal structure. The luminescent property has also been investigated. It shows a blue-purple fluorescence emission.