Spectroscopic investigations on PbO–As₂O₃glasses crystallized with TiO₂

Abstract

PbO-As 2 O 3 glasses mixed with different concentrations of TiO 2 (ranging from 0 to 1.0 mol%) were crystallized. The samples were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy (EDS) techniques. Studies were extended to optical absorption, IR, ESR, luminescence and magnetic susceptibility on these samples. The X-ray diffraction studies reveal the presence of Pb 3 O 4 , Ti(As 2 O 7 ), Pb(As 2 O 6 ), Pb 3 (AsO 4 ) 2 PbTi 3 O 7 and Ti 2 O 3 crystal phases. The optical absorption studies together with ESR and magnetic susceptibility measurements indicated that the titanium ions exist in both Ti 3þ and Ti 4þ states in all the samples and there is an increase in titanium ions in the trivalent state with increasing concentration of nucleating agent TiO 2 . The quantitative analysis of these results indicated that there is a growing degree of disorder in the glass network with increasing concentration of the crystallizing agent. The luminescence studies indicated that the samples crystallized with low concentrations of TiO 2 show high luminescence efficiency in the visible region.

Spectroscopic studies of lead arsenate glasses doped with nickel oxide

“…The broad bands observed in the IR spectra indicate the amorphous nature of the present glasses. The IR spectrum of crystalline As 2 O 3 exhibited 4 fundamental absorption bands ν 1 (1050 cm − 1 ), ν 2 (618 cm − 1 ), ν 3 (795 cm − 1 ) and ν 4 (505 cm − 1 ) which can be attributed to totally symmetric stretching vibrations, totally symmetric bending vibrations, doubly degenerate stretching vibrations and doubly degenerate bending vibrations of AsO 3 structural units respectively [32][33][34][35]. In the infrared spectrum of glass N 0 (pure), bands due to ν 2 vibrations (at 618 cm − 1 ) and the ν 3 vibrations (at 795 cm − 1 ) are observed to be shifted to 620 cm − 1 and 767 cm − 1 respectively; whereas the bands due to ν 1 and ν 4 vibrations are seemed to be missing.…”