A new series of lanthanoid containing Keggin-type germanotungstates with acetate chelators: {Ln(CH(3)COO)GeW(11)O(39)(H(2)O)}(2)](12-) {Ln = Eu(III), Tb(III), Dy(III), Tm(III), and Yb(III)}

Abstract

A series of head-on complexes of lanthanoid containing germanotungstates was isolated from a one pot reaction in an acetate buffer at pH 4.5. This convenient approach brought forward the {Ln(CH(3)COO)GeW(11)O(39)(H(2)O)}(2)](12-) (Ln=Eu(III), Gd(III), Tb(III), Dy(III), Tm(III), and Yb(III)) family with acetate chelators in the rarely observed mu(2): eta(2)-eta(1) mode. All compounds were structurally characterized using various solid state analytics, such as single crystal X-ray diffraction, FT-IR spectroscopy, and thermogravimetric analysis. The isostructural polyanions crystallize in the monoclinic system (S.C. P2(1)/c). Temperature-dependent magnetic susceptibility measurements were performed on the Gd(III)-complex which exhibits near perfect Curie-type behavior. (C) 2010 Elsevier Inc. All rights reserved.