Infrared, Raman spectroscopy and ac magnetic susceptibility of Gd₂O₃-TeO₃-V₂O₅ glasses

In this paper, we present a characterization of the local structure and magnetic properties of the glassy system xGd₂O₃- 65 TeO₂-(35-x)V₂O₅-(x = 2.5, 5, 7.5 mol %) using IR and Raman on one hand, and ac magnetic susceptibility measurements on the other hand. Analysis of IR and Raman spectroscopy indicates to the presence of four main bands attributed to the structural units [TeO₃], [TeO₄], [VO₄], and [VO₅], respectively. The presence of gadolinium cations in the glass structure leads to the appearance of a structural ordering process around the vanadium atoms as well as to a decrease in the number of linked tellurium polyhedra. Thus, it can be said that Gd⁺³ may significantly modify the Te-O network. The ac magnetic susceptibility, the magnetic moment and the Curie temperature, the molecular field constant of these materials were investigated in a temperature range of 4-200K. The reciprocal of the molar magnetic susceptibilities of all samples appear to obey Curie-Weiss law in the paramagnetic region.