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Updated: Jul 14, 2026

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Excited-state dynamics of a methyl-substituted cyclic disulfide
James Merrick1, Claire Vallance1, Adam Kirrander1
1Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK. adam.kirrander@chem.ox.ac.uk.
None:
The effects of methyl substitution on the photodynamics of 1,2-dithiane, a model cyclic disulfide, and the manifestation of these effects in an experimental observable, are investigated theoretically. We employ trajectory surface-hopping simulations initiated on the first excited-state, S1, and compare the dynamic evolution of electronic state populations and nuclear geometries over 1 ps for 1,2-dithiane and its dimethylated analogue, cis-4,5-dimethyl-1,2-dithiane. Additional simulations are performed to disentangle steric and inertial effects on the dynamics in the substituted molecule. Finally, time-resolved valence photoelectron spectra are computed using the Dyson norm approximation. Our study predicts a delayed ring-closing event following initial S-S bond homolysis and an enhanced quantum yield of thiyl radical recombination on the ground-state for the dimethylated system.
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