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Updated: Aug 1, 2026

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
Published on: April 24, 2014
Carotenoid radical cations and dications: EPR, optical, and electrochemical studies
Lowell D Kispert1, Tatyana Konovalova, Yunlong Gao
1Department of Chemistry, University of Alabama, Tuscaloosa, AL 35487-0336, USA. lkispert@bama.ua.edu
Abstract:
Investigations of the structure and properties of paramagnetic carotenoid radical cations and diamagnetic carotenoid dications using electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy in conjunction with electrochemical, optical, and HPLC measurements, and molecular orbital calculations are described. These methods were applied to determine how the carotenoid radical cations and dications can be formed, their electron-transfer properties and stability in various media, and the mechanism by which carotenoid radical cations can isomerize.
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