Heavy atom ferromagnets under pressure: structural changes and the magnetic response.
Masaki Mito1, Yuki Komorida, Hideki Tsuruda
1Faculty of Engineering, Kyushu Institute of Technology, Kitakyushu 804-8550 Japan.
Journal of the American Chemical Society
|October 23, 2009
Summary
Applying physical pressure to ferromagnetic materials can alter their magnetic properties. Increased pressure initially enhances ferromagnetic ordering temperature, but further compression decreases it due to changes in molecular stacking.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Organic Electronics
Background:
- Ferromagnetic organic materials offer potential for novel electronic applications.
- Molecular stacking significantly influences the magnetic properties of such materials.
- Understanding pressure-dependent behavior is crucial for material design.
Purpose of the Study:
- To investigate the effect of physical pressure on the magnetic ordering of a ferromagnetic bisdiselenazolyl radical.
- To correlate changes in pi-stack slippage with the ferromagnetic ordering temperature (T(C)).
Main Methods:
- Application of hydrostatic pressure up to 1 GPa.
- Measurement of ferromagnetic ordering temperature (T(C)) under varying pressures.
- Analysis of pi-stack slippage in response to applied pressure.
Main Results:
- Physical pressure reduces pi-stack slippage in the ferromagnetic bisdiselenazolyl radical.
- The ferromagnetic ordering temperature (T(C)) initially increases with pressure, reaching a maximum of 21 K near 1 GPa.
- At pressures exceeding 1 GPa, T(C) decreases as pi-stacks become more superimposed.
Conclusions:
- Pressure-induced changes in molecular arrangement directly impact the magnetic ordering temperature.
- Optimizing pressure is key to maximizing the ferromagnetic properties of these organic materials.
- This study provides insights into the pressure-dependent magnetism of organic radical ferromagnets.
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