Amorphous solid carbon dioxide

Carbon dioxide gas condensed at 10 K was found to form amorphous solid films whose infrared spectra differ substantially from those of crystalline CO2. With the help of a sample of 13C-enriched CO2, the fundamental absorption bands of different isotopic species of CO2 in the spectra of the amorphous solid, crystalline solid, and of CO2 dispersed in solid nitrogen matrix were analyzed. Some conclusions regarding the structure of the amorphous solid are derived from the spectra.