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Title: Low cation coordination in oxide melts

Abstract

The complete set of Faber-Ziman partial pair distribution functions for a rare earth oxide liquid were measured for the first time by combining aerodynamic levitation, neutron diffraction, high energy x-ray diffraction and isomorphic substitution using Y2 O3 and Ho2 O3 melts. The average Y- O coordination is measured to be 5.5(2), which is significantly less than the octahedral coordination of crystalline Y2 O3 (or Ho2 O3 ). Investigation of high temperature La2 O3 , ZrO2 , SiO2 , and Al2 O3 melts by x-ray diffraction and molecular dynamics simulations also show lower-than-crystal cation- oxygen coordination. These measurements suggest a general trend towards lower M-O coordination compared to their crystalline counterparts. It is found that this coordination number drop is larger for lower field strength, larger radius cations and is negligible for high field strength (network forming) cations. These findings have broad implications for predicting the local structure and related physical properties of metal-oxide melts and oxide glasses.

Authors:
 [1];  [2];  [3];  [2];  [4];  [5];  [6]
  1. State University of New York, Stony Brook
  2. Argonne National Laboratory (ANL)
  3. University of North Texas
  4. ORNL
  5. Materials Development, Inc., Evanston, IL
  6. Stony Brook University (SUNY)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1128979
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 112; Journal Issue: 15
Country of Publication:
United States
Language:
English

Citation Formats

Skinner, Lawrie, Benmore, Chris J, Du, Jincheng, Weber, Richard, Neuefeind, Joerg C, Tumber, Sonia, and Parise, John B. Low cation coordination in oxide melts. United States: N. p., 2014. Web. doi:10.1103/PhysRevLett.112.157801.
Skinner, Lawrie, Benmore, Chris J, Du, Jincheng, Weber, Richard, Neuefeind, Joerg C, Tumber, Sonia, & Parise, John B. Low cation coordination in oxide melts. United States. doi:10.1103/PhysRevLett.112.157801.
Skinner, Lawrie, Benmore, Chris J, Du, Jincheng, Weber, Richard, Neuefeind, Joerg C, Tumber, Sonia, and Parise, John B. Wed . "Low cation coordination in oxide melts". United States. doi:10.1103/PhysRevLett.112.157801.
@article{osti_1128979,
title = {Low cation coordination in oxide melts},
author = {Skinner, Lawrie and Benmore, Chris J and Du, Jincheng and Weber, Richard and Neuefeind, Joerg C and Tumber, Sonia and Parise, John B},
abstractNote = {The complete set of Faber-Ziman partial pair distribution functions for a rare earth oxide liquid were measured for the first time by combining aerodynamic levitation, neutron diffraction, high energy x-ray diffraction and isomorphic substitution using Y2 O3 and Ho2 O3 melts. The average Y- O coordination is measured to be 5.5(2), which is significantly less than the octahedral coordination of crystalline Y2 O3 (or Ho2 O3 ). Investigation of high temperature La2 O3 , ZrO2 , SiO2 , and Al2 O3 melts by x-ray diffraction and molecular dynamics simulations also show lower-than-crystal cation- oxygen coordination. These measurements suggest a general trend towards lower M-O coordination compared to their crystalline counterparts. It is found that this coordination number drop is larger for lower field strength, larger radius cations and is negligible for high field strength (network forming) cations. These findings have broad implications for predicting the local structure and related physical properties of metal-oxide melts and oxide glasses.},
doi = {10.1103/PhysRevLett.112.157801},
journal = {Physical Review Letters},
number = 15,
volume = 112,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 2014},
month = {Wed Jan 01 00:00:00 EST 2014}
}
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