ACETIC-ACID ADSORBED ON COPPER-OXIDE STUDIED BY DOUBLE MODULATION FOURIER-TRANSFORM INFRARED REFLECTION ABSORPTION-SPECTROSCOPY

Acetic acid adsorbed to form the acetate ion on an oxygen preadsorbed copper polycrystalline surface was studied by the use of DM FT-IRAS in the presence or the absence of the vapor phase. The infrared vibrational frequencies for acetic acid adsorbed on oxidized copper are presented. The bands around 2940 cm** minus **1 due to the C-H stretching vibration are not clear while one can clearly cause a weak band to appear by increasing scan times and setting the PEM retardation at 3000 cm** minus **1. These results suggest that one can observe weak bands such as the C-H stretching vibration by increasing scan times and setting the PEM retardation at the appropriate wavelength region.