Vibrational spectra and structure of Li2O-K2O-WO3-B2O3 glasses

Mixed alkali tungsten borate glasses of composition xLi(2)O-(30-x)K2O-10WO(3)-60B(2)O(3) were prepared by melt quench technique. The spectroscopic properties of glass samples were studied using infrared (IR) and Raman spectroscopic techniques. IR measurements indicate that the network structure of the studied glasses is based on the BO3 and BO4 units with W-O-W vibrations in the present glasses. Raman scattering study of the present system to understand the role of the mass of the cation in determining the B-O network in glasses. Raman results show that lighter cations favour a stronger B-O network in which three-dimensional BO4 groups are attached to a large borate ring while the heavy cations are not easily inserted in the network interstices. Acting as complementary spectroscopic techniques, both types of measurements, IR and Raman, revealed that the network structure of the studied glasses is mainly based on BO3 and BO4 units placed in different structural groups, the BO3 units being dominant. (C) 2015 Elsevier Ltd. All rights reserved.