Oxygen sorbed into zeolite

Under usual conditions, molecules such as hydrogen, deuterium, nitrogen and oxygen are IR-inactive, as with respect to their normal mode there does not occur a change in the dipole moment. However, upon adsorption, for instance at the walls of zeolitic channels and cavities, the symmetry of those molecules is disturbed and a dipole is induced by the local electric field. As a first example. Fig. 31 displays the spectra of D2, Nj and O2 sorbed into zeolite Na4Ca4-A [587] at different pressures and (low) temperatures. Calculated geometries of the sor-bate/sorbent complexes are displayed in subsequent figures (vide infra). 

Molecules capable of ionic dissociation, such as H2O and HCN, sorbed in small to moderate quantities into zeolites containing suitable cations, may be substantially dissociated. This may occur by a hydrolysis or dissociative process at the cation, and will be enhanced by the electric fields within the zeolite. The resulting anion coordinates to one or more exchangeable cations to give a larger cationic cluster, and the newly formed cation may move to another site within the zeolite where it can approach anionic charges such as fi amework oxygens. 

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