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arXiv · 2411.10779

The Mechanism of Spin-Phonon Relaxation in Endohedral Metallofullene Single Molecule Magnets

Tanu Sharma·Rupesh Kumar Tiwari·Sourav Dey·Lorenzo A. Mariano·Alessandro Lunghi·Gopalan Rajaraman
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Abstract

This study presents the first-ever investigation of spin-phonon coupling mechanisms in fullerene-based single-molecule magnets (SMMs) using ab initio CASSCF combined with DFT calculations. While lanthanide-based SMMs, particularly those with DyIII ions, are known for their impressive blocking temperatures and relaxation barriers, endohedral metallofullerene (EMFs) offer a unique platform for housing low-coordinated lanthanides within rigid carbon cages. We have explored the spin dynamics of in DyScS@C82 exhibiting among the highest blocking temperature (TB) reported. Through our computational analysis, we reveal that while the fullerene cage enhances crystal field splitting and provides structural stability without significantly contributing to spin-relaxation-driving low-energy phonons, the internal ionic motion emerges as the primary factor controlling spin relaxation and limiting blocking temperature. This computational investigation into the spin dynamics of EMF-based SMMs provides key insights into their magnetic behaviour for the first time an

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Tanu Sharma, Rupesh Kumar Tiwari, Sourav Dey, Lorenzo A. Mariano, Alessandro Lunghi, Gopalan Rajaraman. 2024-11-16. The Mechanism of Spin-Phonon Relaxation in Endohedral Metallofullene Single Molecule Magnets. https://arxiv.org/abs/2411.10779

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