Tracking carbon dioxide adsorbate intramolecular dynamics in pure silica zeolite Silicalite-1 by in situ Raman scattering

Abstract

We report a series of high-quality Raman spectra of carbon dioxide (CO₂) adsorbed at room temperature and at various equilibrium pressures, sampling the corresponding adsorption isotherm up to 1₂ bar. The observed splitting in Fermi diad resonance lines, which were additionally split into two well-resolved components, arising from at least two different CO₂ species, were compared to the same quantity in high-pressure gas/solid/liquid CO₂ phases. Our studies provide material specific spectral data that could be useful in the detection, identification, and dynamical characterization of CO₂ deposits, inclusions, or other forms in remote locations and of various origins, e.g. geological, planetary, stellar, and deap-sea sediments.