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arXiv · 2205.02173

Observation of biradical spin coupling through hydrogen bonds

Yang He·Na Li·Ivano E. Castelli·Ruoning Li·Yajie Zhang·Xue Zhang·Chao Li·Bingwu Wang·Song Gao·Lianmao Peng·Shimin Hou·Ziyong Shen·Jing-Tao Lü·Kai Wu·Per Hedegård·Yongfeng Wang
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Abstract

Investigation of intermolecular electron spin interaction is of fundamental importance in both science and technology.Here, radical pairs of all-trans retinoic acid molecules on Au(111) are created using an ultra-low temperature scanning tunneling microscope. Antiferromagnetic coupling between two radicals is identified by magnetic-field dependent spectroscopy.The measured exchange energies are from 0.1 to 1.0 meV. The biradical spin coupling is mediated through O-H$\cdots$O hydrogen bonds, as elucidated from analysis combining density functional theory calculation and a modern version of valence bond theory.

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Yang He, Na Li, Ivano E. Castelli, Ruoning Li, Yajie Zhang, Xue Zhang, Chao Li, Bingwu Wang, Song Gao, Lianmao Peng, Shimin Hou, Ziyong Shen, Jing-Tao Lü, Kai Wu, Per Hedegård, Yongfeng Wang. 2022-05-04. Observation of biradical spin coupling through hydrogen bonds. https://doi.org/10.1103/physrevlett.128.236401

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