Crystal structure of synthetic zinc monophosphate Zn_2(OH)PO_4: A polymorph of tarbuttite
The syntheses of zinc hydroxyl monophosphate Zn<SUB>2</SUB>(OH)PO<SUB>4</SUB> were carried out under hydrothermal conditions of 573 K and 200 kg/cm<SUP>2</SUP>. The crystal data are: orthorhombic, P2<SUB>1</SUB>2<SUB>1</SUB>2, a=8.099(1), =8.325(1) and c=5.966(1) Å. The structure was solved by three dimensional Patterson syntheses and refined by least squares methods to give a final residual index of R=0.042. There are four units of Zn<SUB>2</SUB>(OH)PO<SUB>4</SUB> in a unit cell and three kinds of zinc atoms with different coordinations, where the first zinc atom is six-coordinated by four oxygen atoms and two hydroxyl groups, the second one is octahedrally coordinated by six oxygen atoms and the third one is five-coordinated by four oxygen atoms and one hydroxyl group forming distorted pyramids. The framework consists of infinite straight chains of Zn–O octahedra along c-axis, connected together by isolated PO<SUB>4</SUB> tetrahedra and distorted Zn–O pyramids. This compound is a polymorph of tarbuttite.
- Mineralogical journal
Mineralogical journal 17(3), 132-139, 1994-07-01
Japan Association of Mineralogical Sciences