Uranium(VI) coordination polymers with pyromellitate ligand: Unique 1D channel structures and diverse fluorescence

Three new coordination polymers of uranium(VI) with pyromellitic acid (H(4)btca) have been synthesized and structurally characterized. (ED)[(UO2)(btca)]center dot(DMSO)center dot 3H(2)O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH4)(2)[(UO2)(6)O-2(OH)(6)(btca)]center dot similar to 6H(2)O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (similar to 8.5 angstrom x similar to 8.6 angstrom). [(UO2)(2)(H2O)(btca)]center dot 4H(2)O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique mu(5)-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (similar to 4.5 angstrom x similar to 19 angstrom). Vibrational modes, thermal stabilities and fluorescence properties have been investigated. Crown Copyright (C) 2015 Published by Elsevier Inc. All rights reserved.