Rare earth coordination dinuclear compounds constructed from 3,5-dicarboxypyrazolate and succinate intermetallic bridges

In this paper we describe the synthesis of a new family of rare earth compounds of general formula [RE 2 (dcpz) 2 (suc)(H 2 O) 8 ]·(H 2 O) 1.5 , where RE = Y ( 1 ), La ( 2 ), Ce ( 3 ), Pr ( 4 ), Nd ( 5 ), Sm ( 6 ), Gd ( 7 ), Tb ( 8 ), Dy ( 9 ), Ho ( 10 ), Er ( 11 ), Tm ( 12 ) and Yb ( 13 ); dcpz = 3,5-dicarboxypyrazolate; suc = succinate. Single crystal X-ray diffraction studies showed that all the complexes are isostructural and crystallize in the triclinic system, space group P 1&cmb.macr;. They exist as dinuclear discrete molecules in which the metallic centers are linked together by dcpz and suc bridges. Hydrogen bonds between dimers give rise to a 3D bcu supramolecular network with topology (4 24 ·6 4 ). Solid-state photoluminescence studies revealed that the ligand-to-metal energy transfer mechanism is responsible for the visible emission of Sm ( 6 ), Tb ( 8 ) and Dy ( 9 ) compounds while for ( 5 ), near-infrared (1060 nm) emission was obtained by the direct excitation f orbitals in the Nd 3+ ion. Magnetization measurements indicated antiferromagnetic interactions between the RE 3+ ions, except Y 3+ ( 1 ) and La 3+ ( 2 ). We describe the synthesis, spectroscopic characterization and photoluminescence studies of a new family of rare earth compounds of formula [RE 2 (dcpz) 2 (suc)(H 2 O) 8 ]·(H 2 O) 1.5 .