Infra-red study of hydrogen-bonding interactions at the solid/liquid interface

Abstract

An infra-red cell is described which enables the measurement of spectra of adsorbed species and the surfaces of powdered solids at the solid/liquid interface. The hydrogen-bonding interactions of acetone, ether and pyridine, adsorbed from carbon tetrachloride solution, with surface hydroxyl groups on silica have been studied. The results are compared with those for the same interactions at the solid/vapour interface. A correlation is observed between the position of the infra-red band due to the OH-stretching vibration of surface hydroxyl groups hydrogen bonded to a series of substituted pyridines and the pK_a values of the corresponding pyridinium ions.