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Glasses of composition xAsO-NaO and xAsO-KO have been prepared and Raman and i.r. spectra studied in relation to the vitreous AsO spectra, previously examined. In glasses richer in AsO, structural centers of vitreous AsO-namely of the claudetitic type-are present together with centers, typical of alkaline metaarsenite structure, which increase as the alkaline oxide percentage increases. Differently from vitreous AsO, which, in time, modifies its structure passing from a claudetitic type to an arsenolitic...

Vibrational spectra of binary glassy materials $A{s}_2{O}_3-PbO$ (Ramanand u.r.), $V_2{O}_5-PbO$ (u.r.) and $A{s}_2{O}_3-V_2{O}_5$ (u.r.) are reported and discussed. In the case of $A{s}_2{O}_3-PbO$ systems, spectra interpretation suggests a modification of $A{s}_2{O}_3$ and $V_2{O}_5$ structures and the formation of structural centers typical, respectively, of metaarsenites and metavanadates. For these demolitions, the probable mechanisms are proposed. In the case of $A{s}_2{O}_3-V_2{O}_5$ system (64-30% of $A{s}_2{O}_3$), the spectra agree with the ortho-, pyro-, metavanadates formation hypothesis together with...