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Journal of Structural Chemistry

, Volume 41, Issue 3, pp 396–402 | Cite as

Structure of the metastable modification of iron(III) oxide

  • E. B. Burgina
  • G. N. Kustova
  • S. V. Tsybulya
  • G. N. Kryukova
  • G. S. Litvak
  • L. A. Isupova
  • V. A. Sadykov
Article

Abstract

A new metastable modification of iron(III) oxide — protohematite — has_been studied. According to the X-ray diffractogram, protohematite (R3c) is identified as hematite (R3c) but characterized by other selection rules for IR and Raman active vibrations. Protohematite does not possess mechanical stability. The protohematite-hematite phase transition is initiated by heating above 900°C, or by pressure application, or by mechanochemical activation. The higher catalytic activity of protohematite compared to hematite may be explained by its structural features, namely, by lowered symmetry of the oxygen sublattice and by the effective tetrahedral environment of some iron cations.

Keywords

Hematite Goethite Thermolysis Mechanochemical Activation Thermolysis Product 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic/Plenum Publishers 2000

Authors and Affiliations

  • E. B. Burgina
    • 1
  • G. N. Kustova
    • 1
  • S. V. Tsybulya
    • 1
  • G. N. Kryukova
    • 1
  • G. S. Litvak
    • 1
  • L. A. Isupova
    • 1
  • V. A. Sadykov
    • 1
  1. 1.G. K. Boreskov Institute of Catalysis, Siberian BranchRussian Academy of SciencesUSSR

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