For a discussion of the structure of greigite, a thiospinel, and its
relationship to the structure of mackinawite, see:
A R Lennie, S A T Redfern, P E Champness, C P Stoddart, P F Schofield, D J
Vaughan (1997) Transformation of mackinawite to greigite: an in situ X-ray
powder diffraction and transmission electron microscopy study. Am Mineral
82: 302-309.
and
R E Krupp (1994) Phase relations and phase transformations between the
low-temperature iron sulfides mackinawite, greigite, and smithite. Eur J
Mineralogy 6: 265-278.
Greigite has the inverse spinel structure, with Fe3+ occupying 100% of the
8(a) sites and 50% (along with 50% Fe2+) of the 16(d) sites. a = 9.876. The
sulfur positional parameter is 0.3755 (in first orientation of space group
in international tables, subtract 1/8 for alternative origin). Structure
given in:
Structure Reports 29, 63 (Skinner et al., 1964)
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Dr Simon Redfern Tel: +44 1223 333475
Dept Earth Sciences Fax: +44 1223 333450
University of Cambridge
Downing Street
Cambridge, CB2 3EQ, UK www.esc.cam.ac.uk/astaff/redfern
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