Bands, vibrational, hydrolytic

Carbon Dioxide Adsorption on Dried Polymer. Other unexpected interactions of these hydrolytic polymers have been noted previously during the measurement of infrared spectra of dried Pu(IV) polymers (like those used for diffraction studies). Vibrational bands first attributed to nitrate ion were observed in samples exposed to room air however, these bands were not present in samples prepared under nitrogen atmospheres (see Fig. 4) (6). Chemical analyses established enough carbon in the exposed samples to confirm the assignment of the extraneous bands to the carbonate functional group... 

From a study of the amount of water formed per molecule of the hydroxide used, Joyner and Kenney concluded that x lies between 10 and 102. The siloxane polymer, a blue air-stable powder is thermally very stable, withstanding 520°C in vacuo for several hours (without subliming) (171). It is also hydrolytically stable, being soluble in concentrated sulfuric acid without decomposition (268). A band at 987 cm-1 in its infrared spectrum is assigned to the Si—O—Si stretching vibration. Further reactions of the dihydroxide are illustrated in Fig. 6. 

As with fused silica, the ultraviolet transmission of Si02 films is dependent on purity. However, the excellent uv transmittance value of purest silica glass cannot even be attained with carefully prepared Si02 films because of incorporated traces of hydrolytic and pyrolytic residues which produce measurable absorption below 205 nm. In the infrared region there are strong absorption bands in the films between 7.8 and 11.5 pm. Those are the same frequencies at which absorption is also observed in pure fused silica. Si-0 vibrations are responsible for this absorption. However, there... 

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