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Updated: May 30, 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
Ab initio lattice dynamics of MnO.
Urszula D Wdowik1, Dominik Legut
1Institute of Technology, Pedagogical University, PL-30-084 Cracow, Poland.
Summary
This study explores MnO lattice vibrations using density functional theory. Increasing Hubbard energies shifts phonon frequencies higher, impacting cation-anion vibrations and heat capacity.
Area of Science:
- Solid State Physics
- Computational Materials Science
- Lattice Dynamics
Background:
- Understanding lattice dynamics is crucial for predicting material properties.
- Manganese oxide (MnO) exhibits complex electronic and magnetic behaviors influenced by its vibrational properties.
Purpose of the Study:
- To investigate the vibrational dynamics of the MnO lattice.
- To analyze the effect of local Coulomb interactions (Hubbard U) on phonon properties.
Main Methods:
- Density Functional Theory (DFT) combined with the direct method.
- Ab initio calculation of Hellmann-Feynman forces.
- Harmonic approximation for vibrational analysis.
Main Results:
- Calculated phonon density of states and dispersion relations for MnO.
- Observed shifts in phonon frequencies to higher values with increased Hubbard energies.
- Demonstrated that on-site Coulomb interactions primarily affect optical phonon modes and cation-anion vibrations.
Conclusions:
- Local Coulomb interactions significantly influence MnO phonon frequencies and vibrational amplitudes.
- Lattice contribution to heat capacity shows minor changes with varying Coulomb repulsion.
- Computational results provide insights comparable to experimental data.
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