Characteristics and long-term kinetics of an azobenzene derivative and a donor-acceptor Stenhouse adduct as orthogonal photoswitches

• Published in: Physical chemistry chemical physics : PCCP Vol. 26; no. 8; pp. 719 - 722
• Main Authors: Schmitt, Tanja, Huck, Christian, Oberhof, Nils, Hsu, Li-Yun, Blasco, Eva, Dreuw, Andreas, Tegeder, Petra
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 22.02.2024
• Subjects: Absorption spectroscopy; Azo compounds; Cross-sections; Infrared spectroscopy; Kinetics; Mixtures; Molecular machines; Quantum mechanics; Room temperature; Smart materials; Switching; Temperature dependence
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/d3cp05786k

Light-triggered molecular switches are extensively researched for their applications in medicine, chemistry and material science and, if combined, particularly for their use in multifunctional smart materials, for which orthogonally, i.e. individually, addressable photoswitches are needed. In such a multifunctional mixture, the switching properties, efficiencies and the overall performance may be impaired by undesired mutual dependences of the photoswitches on each other. Within this study, we compare the performance of the pure photoswitches, namely an azobenzene derivative (Azo) and a donor-acceptor Stenhouse adduct (DASA), with the switching properties of their mixture using time-resolved temperature-dependent UV/VIS absorption spectroscopy, time-resolved IR absorption spectroscopy at room temperature and quantum mechanical calculations to determine effective cross sections, switching kinetics as well as activation energies of thermally induced steps. We find slightly improved effective cross sections, percentages of switched molecules and no increased activation barriers of the equimolar mixture compared to the single compounds. Thus, the studied mixture Azo + DASA is very promising for future applications in multifunctional smart materials. We determined effective cross sections, switching kinetics as well as activation energies of thermally induced steps of an azobenzene derivative (Azo) and a donor-acceptor Stenhouse adduct (DASA) in the single compounds and the mixture Azo + DASA.