Synthesis, structure, and magnetic properties of hydroxo-bridged vanadium oxalate V2O2(OH)(2)(C2O4)(H2O)(2)

The reaction Of V2O5 with H(2)C(2)O(4)(.)2H(2)O in the presence of H3BO3 under hydrothermal conditions has afforded V2O2(OH)(2)(C2O4)(H2O)(2) (1), which crystallizes in the triclinic system, space group P (1) over bar with a = 5.2405(10) angstrom, b = 5.7340(11) angstrom, c = 7.1778(14) angstrom, a = 76.44(3)degrees, beta= 69.37(3)degrees, gamma = 75.37 (3)degrees. The vanadium atoms in I form dimers by sharing edges consisting of p-OH groups, and these dimers are connected further by oxalate ligands to form chains. The magnetic susceptibility data of I fit excellently with the Heisenberg dimer model in the temperature interval 2-300 K. Compound 1 is antiferromagnetic with a J value of -29.6 cm(-1). ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).Chemistry, Inorganic & NuclearSCI(E)6ARTICLE142850-285