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Updated: Jun 11, 2026

Assembly and Characterization of Biomolecular Memristors Consisting of Ion Channel-doped Lipid Membranes
Published on: March 9, 2019
Captodative Radicals Enable the Coexistence of Monomer and Dimer Single-Molecule Junctions with 100-Fold Difference
Weiyi Guo1, Shuai Yao2, Xueling Xu1
1Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong SAR, China.
Abstract:
Atomic-scale manipulation of chemical bond cleavage and formation offers significant advantages of extending the reaction controllability to the single-molecule regime and enabling the elucidation of fundamental reaction mechanisms. Herein, we drive reactions between two chemical species, open-shell monomeric radicals and closed-shell dimers in single-molecule junctions. Both monomers and dimers form a C-Au covalently linked highly conducting junction in situ, with the conductance being about 100× higher than that of the dimer junction. First-principles calculations suggest that the substitution groups on the carbon in the C(sp3)-Au linkage bond effectively tunes the molecular junction conductance. Notably, captodative radicals enable the formation of weakly bonded spin-spin interactions in solution, yielding diamagnetic dimers, and we can reversibly switch between the dimer and the weakly bonded radical pair by mechanically controlling the gap between the two electrodes.
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