INSITU INFRARED EXTERNAL REFLECTION SPECTROSCOPY AS A PROBE OF THE INTERACTIONS AT THE LIQUID SOLID INTERFACE OF LONG-CHAIN ALKANETHIOL MONOLAYERS AT GOLD

The in situ infrared external reflection spectra of a monolayer film of rc-octadecanethiol at gold in aqueous and various nonaqueous solvents are reported. Differences in the peak positions and widths of bands in the C-H stretching region relative to an ex situ (dry N2 atmosphere) spectrum provide preliminary insights into the interactions between solvent and monolayer. Changes in the width and positions of the CH3 stretches, which qualitatively correlate with the polarizability of the solvent, suggest a slight increase in conformational disorder near the chain terminus. © 1990, American Chemical Society. All rights reserved.