Premium
Raman studies of Ag 2 O·WO 3 ·TeO 2 ternary glasses
Author(s) -
Wang C. Y.,
Shen Z. X.,
Chowdari B. V. R.
Publication year - 1998
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/(sici)1097-4555(199809)29:9<819::aid-jrs308>3.0.co;2-v
Subject(s) - crystallization , raman spectroscopy , tetragonal crystal system , ternary operation , materials science , crystallography , crystal (programming language) , mineralogy , chemical engineering , crystal structure , chemistry , optics , physics , computer science , engineering , programming language
A Raman study was carried out on x Ag 2 O·(1‐ x )[ y WO 3 ·(1‐ y )TeO 2 ] ( x =0.3, 0.4) ternary glasses with respect to composition and temperature. The crystallization process and structural units making up the ternary glasses were analyzed in detail. Ag 2 O addition was found to promote the formation of TeO 3 tetragonal pyramid and WO 4 units in the glasses at the expense of TeO 4 tetragonal bipyramid and WO 6 units. The addition of Ag 2 O also lengthens the Te—O bond, whereas WO 3 increases the vibrational wavenumber of the TeO 3 units. The crystallization of the glasses is a two‐step ordering process of the TeO 4 units and complete ordering is hindered by the more rigid WO 4 units. However, the onset of crystallization does not follow a simple pattern with the content of WO 3 . The proportion of the TeO 4 units is always small at the onset of crystallization and increases close to the completion of crystallization, regardless of whether the crystal is formed from the melt by cooling or from the glass state by heating. © 1998 John Wiley & Sons, Ltd.