Structure of (Na2O)x (P2O5)100-x glasses from Infrared reflectance measurements

ORAL

Abstract

IR reflectance has served as a useful complementary probe to Raman scattering on glasses. One observes a phonon near 1172.2 cm-1, associated with the long chains of Q2 species in Raman scattering of c-NaPO3. On the other hand, in g-NaPO3, the corresponding vibrational feature consists of a triad of modes1; a majority mode (1165.6 cm-1) and two minority ones (1151.4 cm-1 and 1105.3 cm-1). These minority modes are weakly excited in Raman but rather strongly in IR TO-response. The minority modes are ascribed to Q1 -like chain terminating topological defects of the long Q2 chains and display a global minimum in concentration in the IP composition range1 ; 37.5% < x < 46.0%. Additionally, when we examine the variation in the LO-TO splitting of the Q2asym (near 1282 cm-1) and Q3 asym (near 1316 cm-1) modes with glass composition ‘x’, one observes a global minimum in the IP range. A similar result is also observed for (Na2O)x (GeO2)100-x glasses2 , suggesting that the reduction of local Electric fields set up in the IP glassy networks could be a general feature.

1. C. Mohanty, M.S. Thesis, University of Cincinnati, 2018.
2. V. Rompicharla, J. Phys. Cond. Matter 20, 202101 2008.

Presenters

  • Vamshi Gogi

    University of Cincinnati

Authors

  • Vamshi Gogi

    University of Cincinnati

  • Avik Mandal

    University of Cincinnati

  • Chandi Mohanty

    University of Cincinnati

  • Mathieu Bauchy

    University of California, Los Angeles, University of California Los Angeles, Univ of California - Los Angeles

  • Matthieu Micoulaut

    University Pierre and Marie Curie, University Pierre et Marie Curie, Univ Pierre et Marie Curie

  • Punit Boolchand

    University of Cincinnati