Molecular Design of Chemically Selective Surfaces Interfacial interactions are critical in areas that are of wide relevance to everyday life.  Examples include adhesion, bio-compatibility, wetting, chemical sensing, and surface adsorption. These interfacial interactions are largely determined by the outermost few nanometers of the surfaces of synthetic and natural materials. Control of interfacial phenomena and expansion of the range of applications requires, therefore, a capability for molecular-level design and engineering of surfaces. Our research group builds on our expertise in the molecular design of surfaces to create smart surfaces.  One focus of our research is surfaces that exhibit chemical selectivity and recognize chemical species by virtue of their shape and molecular size.  To create such selective surfaces, we use host molecules that are bowl-shaped and possess a cavity.  These host molecules are tailored to spontaneously organize into monomolecular assemblies  (self-assembled monolayers).  A fundamental question that our research addresses is the interplay between the “host” molecules in self-assembled monolayer, the structure of “guest” molecule in solution, and the molecular organization of the monolayer and the effect of this interplay on the recognition capability at the solid-liquid interface.  We monitor this recognition using surface sensitive techniques such as polarization modulation IR reflection absorption spectroscopy and surface plasmon resonance.  The goals is to establish principles that will allow use of smart materials and surfaces that interact with their surroundings in applications in electronic devices, separations, and bio-technology.

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