Published online by Cambridge University Press: 01 February 2011
Three novel lanthanum benzenedicarboxylates La2(BDC)3(H2O)4 (1), La4(BDC)3(OH)6 (2) and La3(BDC)2(OH)5 (3) (BDC = 1,4-benzenedicarboxylate) were synthesized by hydrothermal reactions and their structures determined from single crystal X-ray diffraction. All three compounds are 3D framework structures consisting of layers of LaOn polyhedra cross-linked by BDC ligands along the layer stacking direction. In 1 the layers contain separated [LaO6(H2O)2] polyhedra that are bridged by the carboxylate groups of the BDC anions. Compounds 2 and 3 both have highly condensed lanthanum oxide-hydroxide polyhedra. In 2 the layers are wavy and consist of [LaO5(OH)4] and [LaO4(OH)5] polyhedra that share common corners, edges, and faces. In 3, the layers are similar but comprise [LaO3(OH)5] and [LaO4(OH)5] polyhedra.