Synthesis, structural characterization and properties of a novel 1D helical chain arsenomolybdate {[Cu(en)2][Cu(en)(H2O)][(Cu(en)2(H2O)] [AsIIIAsVMo9O34)]} · 2H2O

An organic–inorganic hybrid 1D helical chain arsenomolybdate {[Cu(en)2][Cu(en)(H2O)][(Cu(en)2(H2O)] [AsIIIAsVMo9O34)]} · 2H2O (1) (en = ethylenediamine) has been hydrothermally synthesized and characterized by elemental analyses, IR, UV and CD spectrum, powder X-ray diffraction, TG-DTA and single-crystal X-ray diffraction. The asymmetric unit of 1 consists of a monocapped trivacant Keggin [AsIIIAsVMo9O34]6 − subunit, a pendant [Cu(en)2(H2O)]2 + cation, a pendant [Cu(en)(H2O)]2 + cation, one bridging [Cu(en)2]2 + cation and two lattice water molecules. It should be noted that 1 illustrates a one-dimensional (1D) helical chain assembled by {[Cu(en)(H2O)][(Cu(en)2(H2O)][AsIIIAsVMo9O34)]}2 − clusters and [Cu(en)2]2 + linkers.