Abstract
Two earlier described polymorphous modifications of the cobalt(II) (pseudo)clathrochelate are studied by EPR spectroscopy in the terahertz range, where the complex exhibits the properties of a single-molecule magnet (including the record-breaking barrier for magnetization reversal at the moment). Different values of the magnetization reversal barrier found previously for the corresponding crystalline phases by the results of magnetometric measurements in an alternating magnetic field are observed in the EPR spectra in the terahertz range. A combined analysis of these two methods allows one to more precisely estimate the magnetization reversal barrier for two polymorphous modifications and also the contribution of different magnetic relaxation mechanisms to the spin dynamics. This unambiguously confirms that slight changes in the crystalline environment of the molecule of even such structurally rigid metal complexes as cobalt(II) (pseudo)clathrochelates can result in high differences in the magnetization reversal barrier, which is the key characteristic of single-molecule magnets.
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ACKNOWLEDGMENTS
The cobalt(II) complex was synthesized at the Nesmeyanov Institute of Organoelement Compounds (Russian Academy of Sciences). The synthesis was supported by the Ministry of Science and Higher Education of the Russian Federation.
Funding
This work was supported by the Russian Science Foundation, project no. 17-73-20369.
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Translated by E. Yablonskaya
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Novikov, V.V., Pavlov, A.A., Nehrkorn, J. et al. Influence of Polymorphism on the Magnetic Properties of Single-Molecule Magnets According to the Data of EPR Spectroscopy in the Terahertz Range. Russ J Coord Chem 46, 756–761 (2020). https://doi.org/10.1134/S1070328420110056
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DOI: https://doi.org/10.1134/S1070328420110056