Transmission infrared spectroscopy revealed that the vibrational frequency of CO preadsorbed in linear form at1 298 K on 5% Pt/SiO2 [θCO (average)∼0.3] decreased by 39–44 cm−1 on the coadsorption [298 K, 10 Torr (1 Torr = 133.3 Pa), 30 min] of dioxacycloalkanes, and only by 29–32 cm−1 in the case of oxacyclo-alkanes. The absorbance, integrated absorbance and half-width of the CO band varied during the coadsorption. The change in band shape was also studied on the thermodesorption of CO free from any coadsorbed substance. θCO (local) proved to be of importance in the above coadsorption experiments.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry