A new multi-cobalt-substituted C-shaped polyoxotungstogermanate, [((CoOH2)Co2GeW9O34)(2)(GeW6O26)](20-)

A new multi-cobalt-substituted polyoxogermanotungstate Na-20[((CoOH2)Co2GeW9O34)(2)(GeW6O26)]center dot 47H(2)O has been synthesized and characterized by IR spectroscopy, UV electronic and luminescent spectroscopy, elemental analysis and single-crystal X-ray diffraction. Polyanion [((CoOH2)Co2GeW9O34)(2)(GeW6O26)](20-) consists of two [B-alpha-(CoOH2)Co2GeW9O34](4-) units linked via a unique B-type hexavacant GeW6O2612- fragment, leading to a C-shaped structure with C-2v symmetry. This is the first report of the C-shaped multi-cobalt-substituted polyoxotungstogermanate. (C) 2009 Elsevier B.V. All rights reserved.