HYDROTHERMAL SYNTHESIS, SINGLE-CRYSTAL STRUCTURE, AND MAGNETIC-PROPERTIES OF VOSEO3.H2O

The layered compound VOSeO3.H2O has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. The structure is triclinic, space group P1 with a = 5.969 (2) angstrom, b = 6.155 (2) angstrom, c = 6.349 (2) angstrom, alpha = 92.00 (3)-degrees, beta = 101.88 (2)-degrees, gamma = 117.25 (2)-degrees Z = 2 D(calc) = 3.506 g/cm3, R = 0.0201, and R(w) = 0.0292 for 807 independent diffraction maxima. The structure is formed from layers of vanadium, oxygen, and selenium atoms with coordinated water molecules directed into the interlayer space, resulting in a layer repeat distance (d110BAR) of 5.142 (2) angstrom. The layers contain pairs of V4+O6 octahedra connected through a shared edge, which in turn share corners with SeO3 trigonal pyramids. The connectivity can be represented as VO1/1(H2O)1/1O2/2O2/3SeO2/2O1/3. The magnetic properties are characteristic of antiferromagnetically coupled V4+-V4+ dimers with a coupling constant of J = 27.0 cm-1. The structure of the title compound is compared with those of VOSeO3 and related vanadium phosphates.