Crystal Structure of α-Zn3(VO4)2

Abstract

α-Zn3(VO4)2, the low temperature form of this compound, crystallizes in the orthorhombic space group Cmca with a = 6.088(3), b = 11.489(3), and c = 8.280(3) Å and Z = 4. A total of 726 unique reflections were recorded from integrated precession photographs or with a manually set scintillation counter and used in a full matrix least squares refinement to a final R value of 0.089. The Zn ions lie in two types of octahedral sites while the V ions lie in sites showing tetrahedral coordination to oxygen atoms. The mean V—O bond length is 1.71 Å but one of the V—O bond lengths, involving an oxygen atom bonded to three Zn2+, is 1.78(1) Å long. The average Zn—O bond lengths are 2.13 and 2.10 Å for the Zn ion with site symmetry 2/m and m site symmetry, respectively. α-Zn3(VO4)2 is isostructural with Mg3(VO4)2 and thus has a structure based upon a closest packing of oxygen atoms much like that found in spinel.