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Silver(I) oxide was prepared in a controlled atmosphere by heating a pure, clean silver film in 02 and by reaction with 03. The infrared spectrum consists of one band at 535 cm-1 in the 400-4000-cm-1 region. From this Ag02 film, simple silver carbonate was formed by reaction with C02. It shows four bands at 1410, 1020, 880, and 690 cm-1. The further reaction with water vapor resulted in the formation of basic silver carbonate having peaks at 880, 705, 1060, 1380, and 1460 cm-1, and a broad weak band in the 3200-3400-cm-1 region. The stability of these species with respect to evacuation and heat treatment is also discussed.

Adsorption and subsequent reaction of H2S on alumina gave major i.r. bands at 1341, 1568, 1625, and 3400 cm−1. Relative band intensities were used to follow the first order decomposition of adsorbed H2S and formation of H2O. Rate constants of the surface reaction at 23, 55, and 80 °C were 0.70, 1.48, and 3.42 × 10−3 s−1, respectively. A mechanism consistent with the observed spectral and kinetic data involved adsorption to an exposed Al ion forming an Al—S surface bond, and hydrogen bonding to neighboring O and OH species. It was assumed that the sulfur remained on the surface as a sulfide. The 1568 cm−1 band was discussed in terms of an Al—O species.With adsorption on MoS2–Al2O3, bands appeared at 1330 and 1575 cm−1. Behavior in all respects was similar to that observed on the alumina support alone.

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Diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) and Raman spectroscopy were used to examine N2 and O2 adsorption on cation-exchanged (K, Na, Sr, Ca, and Li) low silica X (LSX) zeolites. IR and Raman absorption bands were observed for the molecular vibration of adsorbed N2 and O2 at room temperature and atmospheric pressure. The intensity (in Kubelka-Munk units) of the IR band increased with N2 pressure and mirrored the adsorption isotherm for N2. Both O2 and N2 displayed a similar dependence of the molecular vibrational frequency on cation charge density, which suggests that both gases are interacting directly with the cations. The vibrational frequencies for adsorbed N2 and O2 were more sensitive to the cation charge density than to framework Al content. Infrared studies of N2 and O2 on mixed cation forms of LSX show that N2 interaction was localized near individual cations within the sorption cavity of the zeolite. Thus, adsorbed N2 can be used to probe accessibility of specific cations within the zeolite framework. The spectroscopic data are consistent with the theory that the stronger interaction of N2 over O2 is caused by the stronger influence of the electric field with the larger quadrupole of N2.

The adsorption of carbon monoxide onto magnesium oxide was investigated. The formation of surface carbonate groups was observed on samples prepared in high vacuum while added oxygen was necessary for carbonate formation with magnesium oxide subject to more vigorous outgassing in ultrahigh vacuum. Carbon dioxide produced similar carbonate species to that formed by carbon monoxide.

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