Home Physical Sciences The structure of metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, by in situ synchrotron powder diffraction
Article
Licensed
Unlicensed Requires Authentication

The structure of metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, by in situ synchrotron powder diffraction

  • Fernando Scordari EMAIL logo , Gennaro Ventruti and Alessandro F. Gualtieri
Published/Copyright: March 28, 2015
Become an author with De Gruyter Brill

Abstract

Metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, is a hydrated sulfate of ferric iron that occurs in sulfate deposits in the desert areas of Northern Chile. The compound used for this study was obtained as a dehydration product of hohmannite, Fe3+2[O(SO4)2]⋅(4+4)H2O. Intensities for the structure analysis were collected from a powdered sample using in situ synchrotron X-ray powder diffraction at ESRF (Grenoble, France). The structure was solved ab initio by profile deconvolution and the application of standard Patterson and difference Fourier maps. The structure was refined to Rp = 5.46% using the Rietveld method. Metahohmannite crystallizes in the triclinic system, space group P1̅

with unit-cell parameters a = 7.3484(5) Å, b = 9.7710(6) Å, c = 7.1521(5) Å, α = 91.684(5)°, β = 98.523 (5)°, γ = 86.390 (5)°, and Z = 2. The structure consists of four Fe3+ octahedra and four sulfate tetrahedra, which share vertices and edges to form a complex building block of Fe3+2[O(SO4)2]⋅8H2O composition. Such blocks are connected to form chains running parallel to the c axis. A complicated system of hydrogen bonds connects adjacent chains into a three-dimensional network. Finally, the crystal structures of metahohmannite, hohmannite, and amarantite are compared and the geometrical features discussed in detail.

Received: 2003-5-23
Accepted: 2003-8-19
Published Online: 2015-3-28
Published in Print: 2004-2-1

© 2015 by Walter de Gruyter Berlin/Boston

Articles in the same Issue

  1. Composition and I4/m-P42/n phase transition in scapolite solid solutions
  2. Synthesis and characterization of K2Ca5(SO4)6·H2O, the equivalent of görgeyite, a rare evaporite mineral
  3. Phase relations in the system Fe-FeSi at 21 GPa
  4. The speciation of dissolved H2O in dacitic melt
  5. Nucleation and growth kinetics of the α-β transformation in Mg2SiO4determined by in situ synchrotron powder X-ray diffraction
  6. Experimental determination of siderite stability and application to Martian Meteorite ALH84001
  7. Determination of the molar absorption coefficient for the infrared absorption band of CO2in rhyolitic glasses
  8. Crystallographic properties of the calcium phosphate mineral, brushite, by means of First Principles calculations
  9. The crystal structure of jonesite, Ba2(K,Na)[Ti2(Si5Al)O18(H2O)](H2O)n: A first example of titanosilicate with porous double layers
  10. Crystal-chemistry of talc: A near infrared (NIR) spectroscopy study
  11. Synthesis of beryllian sapphirine in the system MgO-BeO-Al2O3-SiO2-H2O and comparison with naturally occurring beryllian sapphirine and khmaralite, Part 2: A chemographic study of Be content as a function of P, T, assemblage and FeMg–1exchange
  12. Spriggite, Pb3[(UO2)6O8(OH)2](H2O)3, a new mineral with β-U3O8–type sheets: Description and crystal structure
  13. Sieve-textured plagioclase in dacitic magma: Interference imaging results
  14. Single crystal raman spectroscopy of cerussite
  15. Sodalite: High-temperature structures obtained from synchrotron radiation and Rietveld refinements
  16. The structure of metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, by in situ synchrotron powder diffraction
  17. High-pressure synchrotron X-ray diffraction study of spessartine and uvarovite: A comparison between different equation of state models
  18. Quantum calculations of the electronic structure and NMR quadrupolar interaction parameters for tugtupite
  19. Identification of pyrite valence band contributions using synchrotron-excited X-ray photoelectron spectroscopy
  20. Micro-Raman studies of gypsum in the temperature range between 9 K and 373 K
  21. A new rare earth disilicate (REE2Si2O7; REE = Dy, Tm, Lu; type-L): Evidence for nonquenchable 10 GPa polymorph with silicon in fivefold trigonal bipyramidal coordination?
  22. Structural variations in the brownmillerite series Ca2(Fe2–xAlx)O5: Single-crystal X-ray diffraction at 25 °C and high-temperature X-ray powder diffraction (25 °C ≤ T ≤ 1000 °C)
  23. Peculiarity and defect structure of the natural and synthetic zeolite mordenite: A single-crystal X-ray study
  24. Model independent phase equilibrium constraints on the ferrosilite activity in the binary Fe-Mg orthopyroxene solid solution
  25. Microstructural study of synthetic sintered diamond and comparison with carbonado, a natural polycrystalline diamond
  26. Structural and chemical response to varying [4]B content in zoned Fe-bearing olenite from Koralpe, Austria
  27. A new dense silica polymorph: A possible link between tetrahedrally and octahedrally coordinated silica
  28. Epitaxial relationships of clinopyroxene-hosted magnetite determined using electron backscatter diffraction (EBSD) technique
Downloaded on 22.1.2026 from https://www.degruyterbrill.com/document/doi/10.2138/am-2004-2-316/html
Scroll to top button