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  • The structures of iron silicate glasses with varying iron redox ratios from molecular dynamics simulations and EXAFS analysis
Title: The structures of iron silicate glasses with varying iron redox ratios from molecular dynamics simulations and EXAFS analysis
Iron oxides are frequently found in natural and industrial glass compositions and can affect various physical and chemical properties of the glasses and their melts. Thus, a fundamental understanding of iron-bearing silicate melts and glasses is of both scientific and technological importance. This study investigates the structures of sodium iron silicate glasses with compositions of NaFeSiO4, NaFeSi2O6, NaFeSi3O8, and Na5FeSi4O12 using molecular dynamics simulations in combination with Extended X-ray Absorption Fine Structure (EXAFS) characterizations. Short and medium range structural features of these glasses support that ferrous (Fe2+) and ferric (Fe3+) ions play the roles of network modifier and network former, respectively, with the Fe oxidation states playing an important role in the polymerization of the glass network. These simulation results agree well with newly measured room temperature EXAFS spectra. The simulated glass structures were also compared to the melts structures with the same composition but different redox ratios. The average coordination numbers of the cations were found to be affected both by the melt temperature and iron redox ratio.  more » « less
Award ID(s):
1662288
PAR ID:
10483259
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Non-Crystalline Solids
Volume:
624
Issue:
C
ISSN:
0022-3093
Page Range / eLocation ID:
122713
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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