A vanadium tellurate, (NH(4))(2)[VO(2)](2)[TeO(4)(OH)(2)], containing two edge-shared square-pyramidal VO(5) groups.

A new ammonium vanadium tellurate, (NH(4))(2)VO(2)[TeO(4)(OH)(2)] (1), was hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, and TG analysis. Compound 1 crystallizes in the monoclinic system, space group P2(1)/n: a = 8.9112(18) A, b = 15.151(3) A, c = 15.187(3) A, beta = 97.91(3)(o), V = 2030.9(7) A(3), Z = 8, R1 (I > 2sigma(I)) = 0.0295, wR2 (all data) = 0.0631. The structure of 1 consists of infinite anionic chains, {VO(2)[TeO(4)(OH)(2)]}(2-), of edge-sharing VO(5) square pyramids and TeO(4)(OH)(2) octahedra. Two VO(5) square pyramids are joined together by sharing their edge to form a V(2)O(8) binuclear unit. The V(2)O(8) and TeO(4)(OH)(2) units are alternatively connected to each other by sharing their edges to complete infinite zigzag anionic {VO(2)[TeO(4)(OH)(2)]}(2-) chains. The structure contains an extended network of O-H...O hydrogen bonds between the chains. The network of intermolecular hydrogen bonding results in layers parallel to the ab plane. Ammonium cations are hydrogen-bonded either to the oxygen atoms of the anionic chains or to each other in a complex arrangement.