Crystal growth, structure, and properties of manganese orthovanadate Mn-3(VO4)(2)

Manganese orthovanadate Mn-3(VO4)(2) single crystals were grown for the fir st time from a flux of MnO/V2O5/MoO3. The flux and oxygen partial pressure used are the key factors for the crystal growth and prevention of the oxida tion of Mn2+ and the reduction of V5+ during the crystallization process. T he reduction and oxidation chemistry of Mn-3(VO4)(2) was studied. Mn-3(VO4) (2), is isostructural with magnesium orthovanadate Mg-3(VO4)(2), orthorhomb ic, space group Cmca, a = 6.247(1) Angstrom, b = 11.728(2) Angstrom, c = 8. 491(2) Angstrom and Z = 4, as determined by single crystal X-ray diffractio n. Because it is a Mn2+ deficient spinel structure there are two-dimensiona l sheets of Mn2+O6 octahedra within the structure which show unusual ferrim agnetic properties. (C) 2000 Editions scientifiques et medicales Elsevier S AS. All rights reserved.