Copper ions influence on lead-phosphate glass network

The structure of xCuO center dot(1 - x)[2P(2)O(5)center dot PbO] glass system with 0 <= x <= 50 mol% was investigated by Raman spectroscopy. The characteristic bands of these glasses were identified and analyzed by increasing CuO content. A deconvolution of each Raman spectrum was made in order to make a better identification and assignment of all bands which appear in these spectra Thus, by determining the number of all independent components it was possible to carry out a quantitative analysis of the spectra and also to find the concentration distribution of these components across the investigated glass system. By adding CuO, the symmetric vibration of P-O-P bond in Q(2) groups shifts to higher frequencies due to the depolymerizadon of long phosphate chains and the bands attributed to (PO2)(asym). stretching and (P=O)(sym). stretching vibrations shift to lower frequencies due to the linking of P-O bond to cooper ions. The UV-visible optical absorption results suggest P=O that Cu ions act as a modifier in the studied glasses and may have a possible former role over 20 mol%. Beside this, cooper can be considered as a color center in this glass system. (C) 2013 Elsevier B.V. All rights reserved.