{XW12O40 [Cu(en)2(H2O)]3} (X=V, Si): Two novel tri-supported Keggin POMs with transition metal complexes

Abstract

Two novel polyoxometalate derivatives, {XIVWVI 10WV 2O40[Cu(en)2(H2O)]3} [X=V (1), Si (2); en=ethylenediamine], have been hydrothermally synthesized and characterized by elemental analyses, IR, UV-Vis, XPS, EPR, TG and single crystal X-ray diffraction analyses. They represent the first classical Keggin polyoxoanion supported by three transition metal complex moieties, which further act as the neutral molecular unit for the construction of the interesting three-dimensional supramolecular frameworks. The magnetic properties of 1 have also been studied in the temperature range of 4-300 K, and its magnetic susceptibility obeys the Curie-Weiss law, showing antiferromagnetic coupling. © 2009 Elsevier Inc. All rights reserved.