Related Experiment Video
Updated: Aug 17, 2026

Covalent Fragment Screening Using the Quantitative Irreversible Tethering Assay
Published on: February 28, 2025
Bond breaking coupled with translation in rolling of covalently bound molecules
D L Keeling1, M J Humphry, R H J Fawcett
1School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom.
Abstract:
The response of a C60 molecule to manipulation across a surface displays a long range periodicity which corresponds to a rolling motion. A period of three or four lattice constants is observed and is accompanied by complex subharmonic structure due to molecular hops through a regular, repeating sequence of adsorption states. Combining experimental data and ab initio calculations, we show that this response corresponds to a rolling motion in which two of the four Si-C60 covalent bonds act as a pivot over which the molecule rotates while moving through one lattice constant and identify a sequence of C60 bonding configurations that accounts for the periodic structure.
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