Characterization of Langmuir-Monolayers of Molecular Tweezers and Clips by Means of Brewster-Angle-Microscopy

Abstract

Abstract Molecular clips and tweezers tend to bind selectively electron deficient aromatic and aliphatic substrates. These interesting processes of molecular recognition are usually investigated in dilute solutions of organic or aqueous solvents. Due to discrepancy between polar and hydrophobic groups, molecular clips and tweezers are surface-active chemical compounds which can form monomolecular films at the surface of water. In this publication, we have systematically investigated the self-association and phase-behavior of these artificial receptors by means of pressure-area-isotherms and Brewster-Angle-Microscopy (BAM). We observed spherical and rod-shaped two-dimensional aggregates in the liquid condensed phase. The size and shape of these domains are similar to corresponding structures of classical surfactants.