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Updated: May 28, 2026
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Modelling the non-equilibrium low-temperature magnetic cooling effect in Mn12 clusters
Andrew Palii1, Valeria Belonovich1,2, Denis Korchagin1
1Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Chernogolovka, Moscow Region, 142432, Russian Federation. andrew.palii@uv.es.
Dalton Transactions (Cambridge, England : 2003)
|May 26, 2026
Summary
Researchers predict a novel magnetic cooling effect in Mn$_{12}$ clusters using sudden magnetic field changes. This nonequilibrium method leverages spin relaxation for cooling, unlike conventional magnetocaloric effect (MCE) methods.
Area of Science:
- Condensed Matter Physics
- Quantum Chemistry
- Materials Science
Background:
- Single-molecule magnets (SMMs) like Mn$_{12}$ clusters exhibit unique magnetic properties.
- Conventional magnetocaloric effect (MCE) relies on quasi-static magnetic field changes and entropy cycles.
- Existing MCE methods are often inefficient for SMMs with strong magnetic anisotropy.
Purpose of the Study:
- To theoretically predict and justify a nonequilibrium magnetic cooling effect in Mn$_{12}$ clusters.
- To explore a dynamic cooling regime using sudden magnetic field quenching.
- To identify a novel cooling mechanism applicable to SMMs.
Main Methods:
- Theoretical framework based on spin Hamiltonian dynamics.
- Analysis of relaxation kinetics after sudden magnetic field changes.
- Consideration of Mn$_{12}$Ac as a representative single-molecule magnet.
Main Results:
- Prediction of a nonequilibrium magnetic cooling effect driven by spin relaxation.
- Demonstration that strong magnetic anisotropy, usually detrimental, enhances this novel cooling.
- Identification of a cooling mechanism independent of standard equilibrium entropy cycles.
Conclusions:
- This nonequilibrium approach offers a new pathway for magnetic cooling in SMMs.
- The proposed method is most effective under conditions where conventional MCE is least efficient.
- Strong magnetic anisotropy in SMMs can be advantageous for this dynamic cooling technique.
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