Reversible Photoisomerization of Monolayers of π‐Expanded Oligothiophene Macrocycles at Solid–Liquid Interfaces

Abstract

Self-assembled monolayers of a p-expanded oligothiophene macrocycle undergo photoisomerization between their Z,Z and E,E diastereomers at the interface between octanoic acid solutions and highly oriented pyrolytic graphite (HOPG). The switching process proceeds in situ at the solidliquid interface and was followed by scanning tunneling microscopy( STM). Upon illumination with light at 365 nm (546 nm), amonolayer of Z,Z-8mer (E,E-8mer) photoisomerizes to the E,E-8mer (Z,Z-8mer) form with changes in 2D hexagonal packing.These findings provideinsight towards the design of photoresponsive surfaces with desirable optoelectronic and structural (host-guest) properties.Scheme 1. Chemical structures of Z,Z-8mer and E,E-8mer.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.

Photomodulation of Two-Dimensional Self-Assembly of Azobenzene–Hexa-peri-hexabenzocoronene–Azobenzene Triads

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