(en)Mn2(V2O7): A 3D manganese vanadate built by Mn-O layers and two types of pillars of V2O7 and en bridges

An unexpected 3D manganese vanadate (en)Mn-2(V2O7) (1) (en = ethylenediamine) has been hydrothermally obtained by H2E2Ge2O3 (E= -CH2CH2COO-) ligands and well-prepared mixture of V-Mn-amine and characterized by IR spectroscopy, elemental analysis, thermal stability and powder X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that the structure is a novel pillared-layer, in which MnO5N octahedra are corner-linked to form an infinite sheet with 4-membered rings (MRs) and further condensed to the 3D framework. The most prominent feature of 1 is the connection between the sheets via double bridges, namely, inorganic V2O7 dimeric units and organic en molecules. It is noteworthy that inorganic and organic double bridges between sheets have not been seen in manganese vanadates. (C) 2010 Elsevier B.V. All rights reserved.