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Reversible Photoisomerization of Monolayers of ?-Expanded Oligothiophene Macrocycles at Solid-Liquid Interfaces.

ABSTRACT: Self-assembled monolayers of a ?-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 solid-liquid interface and was followed by scanning tunneling microscopy (STM). Upon illumination with light at 365?nm (546?nm), a monolayer 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 provide insight towards the design of photoresponsive surfaces with desirable optoelectronic and structural (host-guest) properties.

SUBMITTER: Cojal Gonzalez JD

PROVIDER: S-EPMC6582435 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Reversible Photoisomerization of Monolayers of π-Expanded Oligothiophene Macrocycles at Solid-Liquid Interfaces.

Cojal González José D JD Iyoda Masahiko M Rabe Jürgen P JP

Angewandte Chemie (International ed. in English) 20181130 52

Self-assembled monolayers of a π-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 solid-liquid interface and was followed by scanning tunneling microscopy (STM). Upon illumination with light at 365 nm (546 nm), a monolayer of Z,Z-8mer (E,E-8mer) photoisomerizes to the E,E-8mer (Z,Z-8mer) form with change ...[more]

PMID: 30378740

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