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Updated: May 18, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Control over molecular motion using the cis-trans photoisomerization of the azo group
Estíbaliz Merino1, María Ribagorda
1Instituto de Química Orgánica General, Centro Superior de Investigaciones Científicas (CSIC), C/ Juan de la Cierva, 3, 28006, Madrid, Spain.
Abstract:
Control over molecular motion represents an important objective in modern chemistry. Aromatic azobenzenes are excellent candidates as molecular switches since they can exist in two forms, namely the cis (Z) and trans (E) isomers, which can interconvert both photochemically and thermally. This transformation induces a molecular movement and a significant geometric change, therefore the azobenzene unit is an excellent candidate to build dynamic molecular devices. We describe selected examples of systems containing an azobenzene moiety and their motions and geometrical changes caused by external stimuli.
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