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Updated: Jul 26, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Photoswitching of halide-binding affinity and selectivity in dithienylethene-strapped calix[4]pyrrole
David Villarón1, Guido E A Brugman1, Maxime A Siegler2
1Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands. s.j.wezenberg@lic.leidenuniv.nl.
Abstract:
Dithienylethene-strapped calix[4]pyrrole is isomerized by 300/630 nm light between ring-open and -closed isomers, which affects the size of the anion binding site. Where for chloride this results in only a small change in affinity, that of the larger bromide and iodide ions is majorly affected, resulting in altered selectivity.
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