Hydrothermal synthesis and structural characterization of a new vanadyl(IV) arsenate: BaVO(AsO4)(H2AsO4)·H2O

Abstract

A new vanadyl(IV) arsenate, BaVO(AsO₄)(H₂AsO₄)·H₂O, has been synthesised hydrothermally at 230 °C and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and magnetic susceptibility. The compound crystallizes in the monoclinic space group P2₁/n with a= 11.222(2), b= 6.570(2), c= 11.540(3)Å, β= 102.87(2)°, Z= 4 and R= 0.0297. The structure consists of layers of corner-sharing VO₆, AsO₄ and H₂AsO₄ polyhedra, extending parallel to the (101) crystallographic plane with the Ba atoms and H₂O molecules between the layers. The connectivity formula for a layer is _∞²[(VOO_2/2O_3/2)(AsOO_3/2){As(OH)₂O_2/2}]^2–. The adjacent layers are linked by O–Ba–O bonds and hydrogen bonding.