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arXiv · 2101.06161

Magnetic Exchange Interactions in the Molecular Nanomagnet Mn$_{12}$

A. Chiesa·T. Guidi·S. Carretta·S. Ansbro·G. A. Timco·I. Vitorica-Yrezabal·E. Garlatti·G. Amoretti·R. E. P. Winpenny·P. Santini
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Abstract

The discovery of magnetic bistability in Mn$_{12}$ more than 20 years ago marked the birth of molecular magnetism, an extremely fertile interdisciplinary field and a powerful route to create tailored magnetic nanostructures. However, the difficulty to determine interactions in complex polycentric molecules often prevents their understanding. Mn$_{12}$ is an outstanding example of this difficulty: although it is the forefather and most studied of all molecular nanomagnets, an unambiguous determination of even the leading magnetic exchange interactions is still lacking. Here we exploit four-dimensional inelastic neutron scattering to portray how individual spins fluctuate around the magnetic ground state, thus fixing the exchange couplings of Mn$_{12}$ for the first time. Our results demonstrate the power of four-dimensional inelastic neutron scattering as an unrivaled tool to characterize magnetic clusters.

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A. Chiesa, T. Guidi, S. Carretta, S. Ansbro, G. A. Timco, I. Vitorica-Yrezabal, E. Garlatti, G. Amoretti, R. E. P. Winpenny, P. Santini. 2021-01-15. Magnetic Exchange Interactions in the Molecular Nanomagnet Mn$_{12}$. https://doi.org/10.1103/physrevlett.119.217202

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