Reversibility of the supramolecular chirality of bridged binaphtol derivatives at the air-water interface

Second Harmonic Generation (SHG) was used to observe the reversible formation of chiral molecular aggregates at the air-water interface. The aggregates were formed by the chiral bridged binaphthol derivative 1(+) under lateral compression in a Langmuir trough. The S polarized output SHG intensity was measured as a function of the input polarization angle of the fundamental beam during several compression cycles of the molecular film. The chirality of the supramolecular aggregates was established from the non vanishing SHG intensities collected for the p and s input polarization angles. It is demonstrated that the formation of the chiral domains with compression is a reversible process. (C) 2014 Optical Society of America