Raman Scattering and XAFS Study of Optically Nonlinear Glasses of the TiO2-NaPO3-Na2B4O7 System

✍ Scribed by T. Cardinal; E. Fargin; G. Le Flem; M. Couzi

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 286 KB
• Volume: 120
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1995.1390

✦ Synopsis

Raman scattering and (\mathrm{X})-ray absorption studies have been performed on nonlinear optical glasses with compositions (x \mathrm{TiO}{2}, y \mathrm{NaPO}{3}, z \mathrm{Na}{2} \mathrm{~B}{4} \mathrm{O}{7}(y / z=0.95 / 0.05) and (x=0) to (42.2 %) molar). A model is proposed to explain the progressive modifications of Raman and XAFS spectra with increasing (x). Two different types of oxygenated sites for titanium have been identified, in which (T i) is respectively six-fold and five-fold coordinated. The rate of five-fold coordinated (\mathrm{Ti}) is increasing with (x), and the formation of (\mathrm{Ti}-\mathrm{O}-\mathrm{Ti}-\mathrm{O}-\ldots) chains with alternating short and long Ti-O distances have been evidenced for the highest concentrations of (\mathrm{TiO}{2}). (1995 Academic Press, Inc.