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Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition
Published on: February 5, 2022
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Computational materials design of defect-induced ferrimagnetic MnO
Masayoshi Seike1, Tetsuya Fukushima, Kazunori Sato
1Graduate School of Engineering Science, Osaka University, Toyonaka, 560-8531, Japan.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|February 21, 2014
Summary
Computational design revealed that manganese vacancies in manganese oxide (MnO) induce ferrimagnetism. High vacancy concentrations can achieve room-temperature ferrimagnetism, offering a new material design strategy.
Area of Science:
- Computational materials science
- Condensed matter physics
- Solid-state chemistry
Background:
- Manganese oxide (MnO) is typically antiferromagnetic.
- Developing new magnetic materials with tunable properties is crucial for technological applications.
Purpose of the Study:
- To computationally design defect-induced ferrimagnetic states in MnO.
- To investigate the impact of manganese vacancies on MnO's magnetic properties.
Main Methods:
- First-principle calculations using pseudo-self-interaction-corrected local density approximation (PSIC-LDA).
- Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) for random atomic distribution.
- Heisenberg model and magnetic force theorem to calculate exchange coupling constants.
Main Results:
- Manganese vacancies induce ferrimagnetic ground states in MnO.
- Curie temperatures can reach room temperature at vacancy concentrations above 20%.
Conclusions:
- Defect engineering in antiferromagnetic materials can create ferrimagnetic properties.
- This study provides a computational route for designing novel ferrimagnetic materials.
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