Supramolecular Architecture in Langmuir and Langmuir−Blodgett Films Incorporating a Chiral Azobenzene

This article describes the synthesis and fabrication of Langmuir and Langmuir−Blodgett (LB) films incorporating a chiral azobenzene derivative, namely, (S)-4-sec-butyloxy-4′-[5′′-(methyloxycarbonyl)pentyl-1′′-oxy]azobenzene, abbreviated as AZO-C4(S). Appropriate conditions for the fabrication of monolayers of AZO-C4(S) at the air−water interface have been established, and the resulting Langmuir films have been characterized by a combination of surface pressure and surface potential versus area per molecule isotherms, Brewster angle microscopy, and UV−vis reflection spectroscopy. The results indicate the formation of an ordered trilayer at the air−water interface with UV−vis reflection spectroscopy showing a new supramolecular architecture for multilayered films as well as the formation of J aggregates. Films were transferred onto solid substrates, with AFM revealing well-ordered multilayered films without 3D defects. Infrared and UV−vis absorption spectroscopy indicate that the supramolecular architecture...