Structure of lead tellurite glasses and its relationship with stress-optic properties. (February 2019)

• Record Type: Journal Article
• Authors: Kaur, Amarjot; Hirdesh, ; Khanna, Atul; Fábián, Margit; Krishna, P.S.R.; Shinde, A.B.
• Is Part Of: Materials research bulletin. Volume 110(2019)
• Page Start: 239
• Page End: 246
• Publication Date: 2019-02
• Subjects: Lead tellurite glasses -- Neutron diffraction and Reverse Monte Carlo simulation -- Raman spectroscopy -- Short-range structure -- Stress-optic response; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2018.10.008
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Short-range structure of PbO-TeO2 glasses by neutron diffraction, RMC and Raman study. PbO, TeO and OO nearest neighbour distances at 2.79 Ǻ, 1.92 Ǻ and 2.71 Ǻ respectively. PbO decreases TeO coordination in the tellurite network. Structural data predicts lead tellurite glasses to be negative stress birefringent. The predicted stress-optic properties in agreement with experimental results reported in the literature. Abstract: Reverse Monte Carlo (RMC) simulations were applied for modelling the atomic structure of the PbO-TeO2 glasses containing 10, 15 and 20-mol% PbO. The short-range order of the lead-tellurium-oxygen network, involving pair correlation functions of PbO, TeO and OO pairs, the average coordination numbers and the three-particle bond-angle distributions were determined by the RMC analysis. The average PbO coordination is in the range of 5.66 ± 0.19 to 6.02 ± 0.30, whereas TeO coordination (NTe-O ) decreases steadily from 3.55 ± 0.04 to 3.36 ± 0.03 with increase in PbO concentration from 10 to 20 mol%. Raman studies also confirmed that NTe-O decreases on increasing PbO concentration, the latter acts as a modifier and disrupts the local tellurite speciation. The structural parameters are used in the Zwanziger model of stress-optic response to predict that PbO-TeO2 glasses should exhibit negative stress birefringence, a result which is in agreement with the experimental findings reported in the literature.