Effect of Solvent Type on the Infrared Spectrum of Carbon Monoxide Adsorbed Species Selective Gas Chromatographic Detectors

摘要

The infrared spectrum of Carbon Monoxide adsorbed on a platinum electrode from several solvents was investigated. In N-methylformamide, acetonitrile, and 1,2-dichloroethane, the infrared band attributed to linear bonded CO had experimental Stark tuning rates of 20/cm/V, 22/cm/V, and 19/cm/V, respectively. For each of these solvents, the potential dependence of the band position was found to be linear for the entire potential range investigated. When methanol was the solvent, the plot of the band position versus potential had three distinctly linear portions, each with a different value for the slope. The behavior is explained in terms of the ability of the solvent molecules to closely approach the electrode surface, the polarity of the solvent, and the orientation of solvent molecules with respect to the polarization of the electrode. (aw)