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Journal of Thermal Analysis and Calorimetry

, Volume 115, Issue 1, pp 145–151 | Cite as

Thermal decomposition mechanism of iron(III) nitrate and characterization of intermediate products by the technique of computerized modeling

  • P. Melnikov
  • V. A. Nascimento
  • I. V. Arkhangelsky
  • L. Z. Zanoni Consolo
  • L. C. S. de Oliveira
Article

Abstract

The nonahydrate of iron(III) nitrate shows no phase transitions in the range of −40 to 0 °C. Both hexahydrate Fe(NO3)3·6H2O and nonahydrate Fe(NO3)3·9H2O have practically the same thermal behavior. Thermal decomposition of iron nitrate is a complex process which has a different mechanism than those described for other trivalent elements. Thermolysis begins with the successive condensation of 4 mol of the initial monomer accompanied by the loss of 4 mol of nitric acid. At higher temperature, hydrolytic processes continue with the gradual elimination of nitric acid from resulting tetramer and dimeric iron oxyhydroxide Fe4O4(OH)4 is formed. After complete dehydration, oxyhydroxide is destroyed leaving behind 2 mol of Fe2O3. The molecular mechanics method provides a helpful insight into the structural arrangement of intermediate compounds.

Keywords

Iron nitrate Thermal decomposition Oxynitrates Computer modeling 

Notes

Acknowledgements

The authors are indebted to CNPq and FUNDECT (Brazilian agencies) for financial support, and to Prof. Dr. H. Schmidt for fruitful discussions.

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2013

Authors and Affiliations

  • P. Melnikov
    • 1
  • V. A. Nascimento
    • 1
  • I. V. Arkhangelsky
    • 2
  • L. Z. Zanoni Consolo
    • 1
  • L. C. S. de Oliveira
    • 3
  1. 1.School of MedicineFederal University of Mato Grosso do SulCampo GrandeBrazil
  2. 2.School of ChemistryMoscow State UniversityMoscowRussia
  3. 3.School of ChemistryFederal University of Mato Grosso do SulCampo GrandeBrazil

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