Synthesis and Rietveld Crystal Structure Refinement of Mackinawite, Tetragonal FeS

A. R. Lennie*, S. A. T. Redfern†, P. F. Schofield‡ and D. J. Vaughan*
* Department of Earth Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
† Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK
‡ Department of Mineralogy, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK

Abstract: Mackinawite, tetragonal FeS, has been synthesised by reacting iron with Na2S solutions. A Rietveld structure refinement of X-ray powder diffraction data, recorded using X-rays monochromated from synchrotron radiation with a wavelength of 0.6023 Å, has been performed. The structure has been refined in the tetragonal space group, P4/nmm, and has the following cell parameters: a = 3.6735(4), c = 5.0328(7) Å, V = 67.914(24) Å3. Our refinement shows that the FeS4 tetrahedron in mackinawite is almost perfectly regular, with a much smaller distortion than has been previously reported. An improved X-ray diffraction data set is provided.

Keywords: mackinawite • Rietveld structure refinement • synthesis

Mineralogical Magazine; December 1995 v. 59; no. 397; p. 677-683; DOI: 10.1180/minmag.1995.059.397.10
© 1995, The Mineralogical Society
Mineralogical Society (www.minersoc.org)