Synthesis, crystal structures and properties of lanthanide-organic frameworks based benzene carboxylates with two/three-dimensional structure

A series of lanthanide coordination polymers, {[Dy-3(1,3-BDC)(4)(NO3)(Phen)(3)]center dot 2H(2)O}(n) (1), {[DY2(1,3-BDC)(3)(H2O)(2)]center dot H2O}(n) (2), {[Ln(4)(1,3-BDC)(6)(DMF)(H2O)(4)]center dot DMF center dot 2H(2)O}(n) (Ln=Tb (3), Ho (4), Er (5), 1,3-H2BDC=1,3-benzenedicarboxylate, phen=1,10-phenanthroline, DMF=N,N-dimethylformamide), have been synthesized and characterized. In coordination polymer 1, each Dy3+ ion is connected to its neighboring Dy3+ ion through bridging carboxyl oxygen atoms of the 1,3-BDC2- ligands to form a new three-dimensional open-framework structure which the Schlafli symbol of {6(4).8(2)}(2){6(6)}. In coordination polymer 2, center metal dysprosium ions are interlaced and connected through bridging carboxyl oxygen atoms to form an infinite helix chain. Two helix chains are linked through the 1,3-BDC2- ligand to give rise to the two-dimensional layered structure. Coordination polymers 3-5 are isomorphous, which displays a (3,4)-connected net with the point symbol of {4(2) . 6(3) . 8}{4(2) . 6}. The solid-state photoluminescence properties and lifetimes of the Dy (1 and 2) and Tb (3) coordination polymers have been measured at room temperature. (C) 2012 Elsevier Inc. All rights reserved.