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Vibrationally Induced Magnetism in Supramolecular Aggregates
1Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden.
The Journal of Physical Chemistry Letters
|March 6, 2023
Summary
This study proposes a novel mechanism for vibrationally stabilized magnetism, challenging the low-temperature paradigm in condensed matter physics. Anharmonic vibrations at higher temperatures can unexpectedly enhance magnetic properties in chiral structures.
Area of Science:
- Condensed matter physics
- Chemistry
- Supramolecular chemistry
Background:
- Traditional understanding associates magnetic phenomena with low temperatures.
- A critical temperature typically dictates magnetic state stability and strength.
- Recent experiments show enhanced magnetism and chiral-induced spin selectivity with increasing temperature.
Purpose of the Study:
- To propose a mechanism for vibrationally stabilized magnetism.
- To introduce a theoretical model explaining temperature-dependent magnetic phenomena.
- To account for experimental observations in supramolecular aggregates.
Main Methods:
- Theoretical modeling of magnetic states.
- Investigation of anharmonic nuclear vibrations.
- Analysis of structures lacking inversion and/or reflection symmetries.
Main Results:
- A mechanism where anharmonic vibrations stabilize magnetic states is proposed.
- The model explains increased magnetic coercivity with temperature.
- Enhanced chiral-induced spin selectivity is theoretically supported.
Conclusions:
- Anharmonic vibrations, increasingly occupied at higher temperatures, can sustain magnetic states.
- This mechanism is relevant for chiral molecules and crystals lacking inversion/reflection symmetries.
- The findings challenge the conventional low-temperature dependence of magnetism.
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