Contrary to the fairly well established structural chemistry of uranium(VI) with aromatic polycarboxylate ligands, the knowledge on thorium(Th) structural chemistry with this family of ligands is very limited. In this paper, we report the synthesis, spectroscopic and thermal studies, and crystal structures of three Th organic frameworks with 1,2,4,5-benzenetetracarboxylate (btca) or 1,4-benzenedicarboxylate (bdc). Both [Th(btca)(DMF)2(H2O)] (1) and [Th(bdc)2(DMF)2] (2) (DMF = dimethylformamide) have two dimensional (2D) layered structures constructed with 9- (1) or 10- (2) fold coordinated Th polyhedrons and μ4-btca (1) or μ2-bdc (2) ligands, respectively, with two coordinated DMF molecules in cis- (1) or trans- (2) positions on each Th atom. The third phase, [Th(bdc)2] (3), has a 3D pillared framework built with eightfold coordinated Th polyhedrons and μ4-bdc ligands. Their vibrational modes have been investigated and correlated to the structures. VT-PXRD confirmed that 3 is thermally robust to 500 °C and the weight loss at ∼300 °C is due to the loss of water molecules in the solvent accessible voids in the crystal lattice.
|Number of pages||10|
|Journal||Journal of Inclusion Phenomena and Macrocyclic Chemistry|
|Publication status||Published - Jun 2015|
- X-ray diffraction