2 NEW BARIUM VANADIUM(IV) PHASES - BA(VO)(2)(SEO3)(2)(HSEO3)(2), THE FIRST BARIUM VANADIUM SELENITE, AND BA-8(VO)(6)(PO4)(2)(HPO4)(11)CENTER-DOT-3H2O, A COMPOUND BUILT-UP FROM 2 TYPES OF ONE-DIMENSIONAL CHAINS

The hydrothermal syntheses, X-ray single-crystal structures, and some properties of Ba(VO)(2)(SeO3)(2)(HSeO3)(2) and Ba-8(VO)(6) (PO4)(2)(HP O4)(11). 3H(2)O are described. Ba(VO)(2)(SeO3)(2)(HSeO3)(2) contains a three-dimensional network of VO6 and (H)SeO3 polyhedra, linked via V- O-Se bonds. The Ba cation is 10-coordinate, the VO6 group contains a s hort vanadyl V=O bond typical of V-IV, and the (H)SeO3 groups are pyra midal. Magnetic susceptibility data are consistent with V-IV and show paramagnetic behavior from 4 to 300 K. Crystal data for Ba(VO)(2)(SeO3 )(2)(HSeO3)(2): M(r) = 781.06, monodinic, space group P2(1)/c (No. 14) , a = 9.680(3) Angstrom, b = 7.024(2) Angstrom, c = 9.882(4) Angstrom, beta = 116.42(3)degrees, V = 601.75 Angstrom(3), Z = 2, R = 3.89%, R( W) = 3.64% [1637 observed reflections with I > 3 sigma(I)]. Ba-8(VO)(6 )(PO4)(2)(HPO4)(11). 3H(2)O contains a complex network of VO6 and PO4/ HPO4 groups, which form two different types of one-dimensional chains: one chain contains fairly regular (VO6)-O-IV and (H)PO4 groups; the o ther is built up from distorted (VO6)-O-IV octahedra and (hydrogen) ph osphate groups. 10- and 13-coordinate Ba2+ cations complete the struct ure, which shows antiferromagnetic ordering of the V-IV centers at sim ilar to 20 K. Crystal data for Ba-8(VO)(6)(PO4)(2)(HPO4)(11). 3H(2)O: M(r) = 2800.05, monoclinic, space group C2/m (No. 12), a = 31.685(11) Angstrom, b = 5.208(2) Angstrom, c = 7.784(3) Angstrom, beta = 90.59(3 )degrees, V = 1284.5(7) Angstrom(3), Z = 1, R = 4.03%, and R(W) = 5.28 % [1892 observed reflections with I > 3 sigma(I)]. (C) 1995 Academic P ress, Inc.