No abstract

Reduction processes of Ti 4+ ions in various silicate glasses have been studied by EPR spectroscopy at 20 K. Different parameters like the [Na]/[Ti] ratio, the integrated dose and Ti 3+ ions ageing processes were analyzed in this work. Simulation of the Ti 3+ ion EPR spectra in different Ti-doped silicate glasses has shown three different Ti 3+ environments attributed to one [VI] Ti 3+ and two [V] Ti 3+ environment (square pyramid and trigonal bi-pyramid). The [VI] Ti 3+ ion environment is observed only for [Na]/[Ti] ratios higher or equal to 68 although the two others are observed for all values of the [Na]/[Ti] ratio considered. In terms of relative proportions, the Ti 3+ ions in a square pyramid of oxygen are the dominant species.