6533b837fe1ef96bd12a1e9f

RESEARCH PRODUCT

Photoresponsive Halogen-Bonded Liquid Crystals: The Role of Aromatic Fluorine Substitution

Matthias SpenglerMatti VirkkiMarco SacconeKim KuntzeChristoph WölperPierangelo MetrangoloRobert GehrkeMichael PfletscherGeorg JansenMichael GieseArri Priimagi

subject

Materials scienceHalogen bondPhotoisomerizationGeneral Chemical EngineeringSupramolecular chemistryChemiechemistry.chemical_elementMesophase02 engineering and technologyGeneral Chemistry010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciences0104 chemical scienceschemistry.chemical_compoundAzobenzenechemistryLiquid crystalHalogenMaterials ChemistryFluorineHalogen Bonding Fluorine Liquid Crystals Photoresponsive MaterialsSettore CHIM/07 - Fondamenti Chimici Delle Tecnologie0210 nano-technology

description

A new strategy for controlling the liquid crystalline and photophysical properties of supramolecular mesogens assembled via halogen bonding is reported. Changing the degree of fluorination at the halogen-bond donor of the supramolecular liquid crystal allows for the fine-tuning of the halogen bond strength and thereby provides control over the temperature range of the mesophase. At least three fluorine atoms have to be present to ensure efficient polarization of the halogen-bond donor and the formation of a mesophase. In addition, it was found that stilbazole acceptors are superior to their azopyridine counterparts in promoting stable liquid crystalline phases. The halogen-bond-driven supramolecular liquid crystals between fluorinated azobenzenes and stilbazole/azopyridine acceptors show a rich variety of photoinduced processes driven by azobenzene photoisomerization, dictated not only by the photochemical properties of the molecular components but also by the difference between the operation temperature and the clearing point

10.1021/acs.chemmater.8b04197http://hdl.handle.net/10447/398742