Crystal growth and structure of a new manganese vanado-antimonate MnVSbO6

摘要

Single crystals of a new compound of formula MnVSbO6 were grown by slow cooling from a V2O5-B(2)O3(3) flux at 900degreesC. The compound crystallizes in the orthorhombic space group Pbcn (No. 60), with cell parameters (in the Pcnb setting) a = 4.6604(3) Angstrom, b = 4.9603(3) Angstrom, c = 17.1433(9)Angstrom, Z = 4. The crystal structure was solved from 1188 independent reflections to R-w = 3.20% and goodness-of-fit 1.5 for 44 refined parameters. The structure can be described as a superstructure of the alpha-PbO2 type with a cation ordering similar to that found in Fe2WO6. Cations occupy octahedral sites in the PbO2-like layers. Zigzag chains of edge-sharing MnO6 octahedra alternate with mixed Sb/V chains following a -Mn-Sb/V-Sb/V- sequence. The magnetic susceptibility of MnVSbO6 follows the Curie-Weiss law down to ca. 15 K, where it orders antiferromagnetically. The bond lengths and Curie constant are consistent with the expected charge distribution Mn2+V5+Sb5+O6. (C) 2003 Elsevier Inc. All rights reserved. [References: 22]