Effect of resonance dipole–dipole interaction on spectra of adsorbed SF6 molecules

• Spectra of adsorbed SF6 depend on the mutual arrangement of interacting molecules.
• Adsorbed molecules form an one-dimensional (1D) and two-dimensional (2D) systems.
• The dynamic interaction (RDDI) is manifested as the doublet spectral band structure.
• Components correspond to transversal and longitudinal vibrations of dipole moment.
• Maximal RDD splitting between components for 1D chains is smaller than for 2D flat.

Adsorption of SF6 on zinc oxide and on silicalite-1 was investigated by a combination of IR spectroscopy with the calculations of spectra by means of a modernized model, developed previously for liquids. Comparison of the experimental spectra and the results of modeling shows that the complex band shapes in spectra of adsorbed molecules with extremely high absorbance are due to the strong resonance dipole–dipole interaction (RDDI) rather that the surface heterogeneity or the presence of specific surface sites. Perfect agreement between calculated and observed spectra was found for ZnO, while some dissimilarity in band intensities for silicalite-1 was attributed to complicated geometry of molecular arrangement in the channels.

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