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Updated: Jun 24, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
A theoretical investigation of alpha-Fe2O3-Cr2O3 solid solutions
Sreelekha Benny1, Ricardo Grau-Crespo, Nora H de Leeuw
1Department of Chemistry, University College London, London, UK WC1H 0AJ.
Physical Chemistry Chemical Physics : PCCP
|March 18, 2009
Summary
The thermodynamic stability of iron(III) oxide-chromium(III) oxide solid solutions was investigated. Highly disordered solutions are stable above 400 K due to a small positive enthalpy of mixing.
Area of Science:
- Materials Science
- Thermodynamics
- Computational Chemistry
Background:
- Understanding the thermodynamic stability of mixed metal oxides is crucial for designing new materials.
- Alpha-Fe2O3-Cr2O3 solid solutions are of interest for various industrial applications.
Purpose of the Study:
- To investigate the thermodynamic stability of alpha-Fe2O3-Cr2O3 solid solutions.
- To determine the influence of temperature, composition, and magnetic interactions on solid solution stability.
Main Methods:
- Combined statistical mechanics and atomistic simulations using classical interatomic potentials.
- Incorporated a model magnetic interaction Hamiltonian.
- Analyzed cation disorder and effective cell parameters.
Main Results:
- Segregation of Fe and Cr cations is only marginally favorable energetically.
- The energy of mixed configurations is slightly higher than pure oxides.
- Positive enthalpy of mixing is small, allowing disordered solid solutions above ~400 K.
Conclusions:
- Highly disordered alpha-Fe2O3-Cr2O3 solid solutions can be stabilized at elevated temperatures.
- Magnetic interactions and lattice vibrations play a role in solid solution stability.
- The findings provide insights into the phase behavior of these mixed oxide systems.
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