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Title: Structure of Liquid SiO{sub 2}: A Measurement by High-Energy X-Ray Diffraction

Abstract

The x-ray structure factor for liquid SiO{sub 2} has been measured by laser heating of an aerodynamically levitated droplet. The main structural changes of the melt compared to the room temperature glass are associated with an increase in the size of the SiO{sub 4} tetrahedra, indicating a small reduction in the average Si-O-Si bond torsion angle and an expansion of the network between 5 and 9 A ring . Strong directional bonds with little high temperature broadening and a high degree of intermediate range order are found to persist in the liquid state.

Authors:
 [1];  [1];  [2];  [3]
  1. Intense Pulsed Neutron Source Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
  2. (United States)
  3. Containerless Research, Inc., Evanston, Illinois 60202 (United States)
Publication Date:
OSTI Identifier:
20955431
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevLett.98.057802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHEMICAL BONDS; DROPLETS; LASER-RADIATION HEATING; SILICON OXIDES; STRUCTURE FACTORS; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TORSION; X-RAY DIFFRACTION

Citation Formats

Mei, Q., Benmore, C. J., X-Ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, and Weber, J. K. R. Structure of Liquid SiO{sub 2}: A Measurement by High-Energy X-Ray Diffraction. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.057802.
Mei, Q., Benmore, C. J., X-Ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, & Weber, J. K. R. Structure of Liquid SiO{sub 2}: A Measurement by High-Energy X-Ray Diffraction. United States. doi:10.1103/PHYSREVLETT.98.057802.
Mei, Q., Benmore, C. J., X-Ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, and Weber, J. K. R. Fri . "Structure of Liquid SiO{sub 2}: A Measurement by High-Energy X-Ray Diffraction". United States. doi:10.1103/PHYSREVLETT.98.057802.
@article{osti_20955431,
title = {Structure of Liquid SiO{sub 2}: A Measurement by High-Energy X-Ray Diffraction},
author = {Mei, Q. and Benmore, C. J. and X-Ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439 and Weber, J. K. R.},
abstractNote = {The x-ray structure factor for liquid SiO{sub 2} has been measured by laser heating of an aerodynamically levitated droplet. The main structural changes of the melt compared to the room temperature glass are associated with an increase in the size of the SiO{sub 4} tetrahedra, indicating a small reduction in the average Si-O-Si bond torsion angle and an expansion of the network between 5 and 9 A ring . Strong directional bonds with little high temperature broadening and a high degree of intermediate range order are found to persist in the liquid state.},
doi = {10.1103/PHYSREVLETT.98.057802},
journal = {Physical Review Letters},
number = 5,
volume = 98,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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