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Updated: Aug 8, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
The theory of non-Cottrellian diffusion on the surface of a sphere or truncated sphere
Mary Thompson1, Gregory G Wildgoose, Richard G Compton
1Physical and Theoretical Chemistry Laboratory, Oxford University South Parks Road, Oxford, OX1 3QZ, UK.
Abstract:
A method is developed whereby spherical and other particles can be derivatised with electroactive species on their surface and then immobilised on the surface of an electrode. The chronoamperometric and voltammetric responses in the limit of reversible electrode kinetics are modelled using a theory of charge movement over the surface of the spheres where this movement is considered as a diffusional process. The model is extended to include different distributions of sphere radii and to model the scenario of truncated spheres resting on the electrode surface. It is found that a good estimation of the truncation angle can be found by fitting the experimental data with theoretical predictions.
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