Perturbation of the infrared absorption spectra of aromatic adsorbates in microporous carbons by the Christiansen effect

Abstract

The infrared spectra of aromatic adsorbates held in activated carbon can show large band asymmetries that appear to originate from index of refraction matching between adsorbate and the carbon surrounding the micropores. The magnitude of the effect is quite sensitive to carbon structure, adsorbate concentration, and wavelength but appears to be independent of the particle shape and surrounding medium, e.g., KBr or air. It is proposed that the effect can be used to differentiate microporous carbons and to probe the structure of their internal surfaces. © 1987 American Chemical Society.