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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...

Raman spectra of materials of binary molar composition BO/LiO variable between 9 and 1 in the glassy system BO-LiO are discussed relatively to the "boric anomaly" phenomenon presented by these glasses and relatively to the measures of diamagnetic anisotropy and nuclear magnetic resonance made by other Authors. In analogy to these latest measures the presence of structural centers consisting of boroxol groups BO(O) is made evident in the glasses richest in BO up to the composition 3BO-LiO. Moreover...

Infrared spectra of aqueous solutions of dimethylsulphoxide (DMSO) in a wide range of concentrations are presented and discussed. The present work is preliminary to a wider research including Raman laser and near infrared vibrational investigations. In the infrared spectra it is possible to observe the presence of at least three ${\nu }_{So}$ components in a certain range of more concentrated solutions, and the presence of a single ${\nu }_{So}$ component in the case of more dilute solutions. As a preliminary hypothesis,...