X-ray powder diffraction structural characterization of iron(III) chloro- and bromo-complexes of triphenylphosphine oxide

• Published in: Crystal research and technology (1979) 2003-02, Vol.38 (2), p.174-181
• Main Authors: Jorík, V., Ondrejkovicová, I., von Dreele, R. B., Ehrenberg, H.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Inorganic compounds; iron(III) complexes; Metal complexes; Physics; powder diffraction; Rietveld refinement; rigid body; Single-crystal and powder diffraction; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; X-ray diffraction and scattering
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/crat.200310020

Iron (III) complexes of the composition [FeX2(OPPh3)4][FeX4], where X is Cl or Br were synthesised by several methods. It was found that each particular synthesis has yielded solids with slightly different powder patterns and also their comparison to those of calculated from single crystal data showed remarkable differences. A series of constrained Rietveld refinements has been performed on the title complexes to explain these differences. In a course of Rietveld refinement it was found that preferred orientation is not the only factor affecting the shape of the pattern and atoms parameters were included into refinement too. The results of Rietveld refinement allowed to conclude that the structures of compounds prepared by different methods are identical. In addition, it was shown that also in the case of rather complicated structure like the title complexes the powder diffraction method can lead to reasonable results.