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Author Spotlight: Functionalizing Metal-Organic Frameworks: Advancements, Challenges, and the Power of Post-Synthetic Ligand Exchange
Published on: June 23, 2023
Multi-functional switches of ditopic ligands with azobenzene central bridges at a molecular scale
Hnid Imen1, Sun Xiaonan1, Frath Denis2
1Université de Paris, ITODYS, CNRS, UMR 7086, 15 rue J-A de Baïf, F-75013 Paris, France. Sun.xiaonan@univ-paris-diderot.fr.
Abstract:
Ligands are designed to have ditopic bipyridine terminal groups linked through photochromic azobenzene central units, which exhibit multi-switchable properties by different external stimuli. The molecule can switch between cis-and trans-conformations at their bipyridine terminal groups upon protonation and at their central azobenzene units upon irradiation of photons. As a result, the system shows four different isomeric states: cis-TRANS, trans-TRANS, cis-CIS and trans-CIS. The four conformers are switched and are visualized by scanning tunneling microscopy at the solid-liquid interface, which gives a direct demonstration of the multi-functional switches at a molecular level.
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