Acta Cryst. (2005). E61, i135-i136 [ doi:10.1107/S1600536805020507 ]
Abstract: The crystal structure of the mineral polyhalite, or dipotassium dicalcium magnesium tetrakis[sulfate(VI)] dihydrate, was reinvestigated by means of single-crystal X-ray diffraction data. The structural model previously reported was confirmed, although a higher precision of the refinement has been achieved. The structure consists of K and Ca polyhedra and [MgO4(H2O)2] octahedra sharing edges and faces; SO4 tetrahedra share edges with the polyhedra.
Online 6 July 2005
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