Crystal Growth and Structure Determination of Pigment Orange 82

The crystal structure of the important industrial orange pigment PO82, major part of the BASF Colors & EffectsA (R) product SicopalA (R) Orange K/L 2430, was solved from combined X-ray single crystal, X-ray and neutron powder diffraction, Sn-119 Mossbauer spectroscopy, transmission electron microscopy, electron diffraction, and chemical analyses. The structure contains Keggin type clusters composed of four [M3O13] trimers consisting each of three MO6 octahedra that share edges and one common oxygen atom connecting the trimers to the central ZnO4 tetrahedron. The octahedrally coordinated metal atom position is mixed occupied by Ti4+, Sn4+, and Zn2+. Adjacent Keggin clusters share vertices and are further interconnected to four ZnO4 tetrahedra. This framework of interconnected MO6 octahedra and ZnO4 tetrahedra contains channels along [110], in which the Sn2+ cations are located.