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Updated: Feb 12, 2026

Light-driven Molecular Motors on Surfaces for Single Molecular Imaging
Published on: March 13, 2019
Thermal E/ Z Isomerization in First Generation Molecular Motors
Shunsuke Kuwahara1,2, Yuri Suzuki1, Naoya Sugita1
1Department of Chemistry, Faculty of Science , Toho University , 2-2-1 Miyama , Funabashi , Chiba 274-8510 , Japan.
Abstract:
Determination of a thermal E/ Z isomerization barrier of first generation molecular motors is reported. Stable ( E)-1a directly converts to stable ( Z)-1c without photochemical E/ Z isomerization. The activation Gibbs energy of the isomerization was determined to be 123 kJ mol-1 by circular dichroism spectral changes. Density functional theory calculations show that ( Z)-1c is ∼11.4 kJ mol-1 more stable than ( E)-1a.
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