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arXiv · 2504.18043

Magnetic Resonance Imaging of Single Organic Radicals with Sub-Molecular Resolution

Gregory Czap·Christoph Wolf·Jose Reina-Gálvez·Mark H. Sherwood·Christopher P. Lutz
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Abstract

Interest in the magnetism of organic compounds is growing because of new organic magnets, spin-based electronics and the diverse properties of magnetic edge states in graphene nanoribbons. Electron spin resonance spectroscopy combined with the scanning tunneling microscopy has recently been developed as a powerful tool to address individual magnetic atoms and molecules at the atomic scale. Here we demonstrate electron spin resonance and magnetic resonance imaging of all-organic radical anions adsorbed on a protective thin insulating film grown on a metal support. We show that using the highly localized exchange field of the magnetic tip apex allows visualization of the delocalized spin density with sub-molecular resolution, enabling spin-density tomography that can distinguish similar molecular species. These results provide new opportunities for visualizing spin density and magnetic interactions at the atomic scale.

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Gregory Czap, Christoph Wolf, Jose Reina-Gálvez, Mark H. Sherwood, Christopher P. Lutz. 2025-04-25. Magnetic Resonance Imaging of Single Organic Radicals with Sub-Molecular Resolution. https://arxiv.org/abs/2504.18043

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