gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1977.041.319.10 The Crystal Structure of Ferrinatrite, Na3(H2O)3[Fe(SO4)3] and Its Relationship to Maus's Salt, (H3O)2K2{K0.5(H2O)0.5}6[Fe3O(H2O)3(SO46](OH)2 Scordari F. Istituto di Mineralogia e Petrografia dell'Università di Bari, Italy 9 1977 41 319 375 383 20 4 1976 14 10 1976 Copyright © 1977, The Mineralogical Society 1977 Summary

Ferrinatrite crystallizes in space group P3¯, with a = 15·566(5), c = 8·69(1) Å, and Z = 6. The crystal structure was solved by three-dimensional Patterson and Fourier syntheses, and refined by least squares employing 2378 independent reflexions to a final R value of 0·068. The iron ions occupy special positions and are surrounded octahedrally by oxygen atoms. Fe3+O6 octahedra and SO4, tetrahedra are linked together to form infinite chains of Fe-O-S linkages in the [0001] direction. These chains are linked to each other by [NaO5(H2O)2] polyhedra and probably by hydrogen bonds. The topology of the arrangement is the same as that of the hypothetical P312 structure proposed by Moore and Araki (1974).