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Updated: Jun 20, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
The photochemical trans → cis and thermal cis → trans isomerization pathways of azobenzo-13-crown ether: A
Dilawar Singh Sisodiya1, Anjan Chattopadhyay1
1Department of Chemistry, Birla Institute of Technology and Science (BITS), Pilani, K. K. Birla Goa Campus, Zuarinagar, India.
Abstract:
The isomerization of azobenzo-13-crown ether can be expected to be hindered due to the polyoxyethylene linkage connecting the 2,2'-positions of azobenzene. The mixed reference spin-flip time-dependent density functional theory results reveal that the planar and rotational minima of the first photo-excited singlet state (S1) of the trans-isomer pass through a barrier (2.5-5.0 kcal/mol) as it goes toward the torsional conical intersection (S0/S1) geometry (
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