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Updated: Jun 4, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Comparative ab initio study of lattice dynamics and thermodynamics of Fe2SiO4- and Mg2SiO4-spinels
Mariana Derzsi1, Przemysław Piekarz, Kamil Tokár
1Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, PL-31342 Kraków, Poland.
Abstract:
Lattice dynamics and thermodynamic properties of antiferromagnetic Fe(2)SiO(4)-spinel have been studied using density functional theory. Phonon dispersions are obtained for several hydrostatic pressures up to 20 GPa. They are used to calculate thermodynamic properties within the quasiharmonic approximation. Comparison with ab initio results obtained for Mg(2)SiO(4)-spinel is made in order to study the effect of the cation exchange on the dynamic and thermodynamic properties of (Mg, Fe)(2)SiO(4)-spinel. The obtained results have been compared with the available experimental data.
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