skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F

Abstract

The structural details of the ordered hexagonal oxyfluoride Na{sub 2}CaVO{sub 4}F prepared by solid-state synthesis using stoichiometric amounts of V{sub 2}O{sub 5}, CaCO{sub 3}, Na{sub 2}CO{sub 3} and NaF were characterized using high-resolution neutron powder diffraction. The structural changes between 25 °C and 750 °C revealed that the two structural subunits in this material behave different when heated: there is an expansion of the face-shared FNa{sub 4}Ca{sub 2} octahedra while the VO{sub 4} tetrahedra due to increased thermal disorder reveal marginal bond contractions. Bond valences and the global instability index point to significant structural disorder at 750 °C. - Graphical abstract: The structure of the novel oxyfluoride Na{sub 2}CaVO{sub 4}F is studied at room temperature and high-temperatures. The structure can be viewed as layers of compression and elongation of polyhedral subunits, which change as a function of temperature. - Highlights: • The novel oxyfluoride, Na{sub 2}CaVO{sub 4}F, is synthesized via solid-state method. • High-resolution neutron diffraction data is used to analyze the structure of Na{sub 2}CaVO{sub 4}F. • Structural subunits exhibit expansion and contraction with increasing temperature. • Higher temperatures increase instability within the structure of Na{sub 2}CaVO{sub 4}F.

Authors:
 [1];  [2]
  1. Australian Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)
  2. NanoCenter and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States)
Publication Date:
OSTI Identifier:
22658297
Resource Type:
Journal Article
Journal Name:
Journal of Solid State Chemistry
Additional Journal Information:
Journal Volume: 250; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0022-4596
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CALCIUM CARBONATES; CARBON IONS; NEUTRON DIFFRACTION; OXYFLUORIDES; SODIUM CARBONATES; SODIUM FLUORIDES; SYNTHESIS; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; VANADIUM OXIDES

Citation Formats

Green, Robert L., E-mail: rgreen@flpoly.org, Avdeev, Maxim, School of Chemistry, The University of Sydney, Sydney, NSW 2006, and Vogt, Thomas. Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F. United States: N. p., 2017. Web. doi:10.1016/J.JSSC.2017.03.027.
Green, Robert L., E-mail: rgreen@flpoly.org, Avdeev, Maxim, School of Chemistry, The University of Sydney, Sydney, NSW 2006, & Vogt, Thomas. Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F. United States. https://doi.org/10.1016/J.JSSC.2017.03.027
Green, Robert L., E-mail: rgreen@flpoly.org, Avdeev, Maxim, School of Chemistry, The University of Sydney, Sydney, NSW 2006, and Vogt, Thomas. 2017. "Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F". United States. https://doi.org/10.1016/J.JSSC.2017.03.027.
@article{osti_22658297,
title = {Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F},
author = {Green, Robert L., E-mail: rgreen@flpoly.org and Avdeev, Maxim and School of Chemistry, The University of Sydney, Sydney, NSW 2006 and Vogt, Thomas},
abstractNote = {The structural details of the ordered hexagonal oxyfluoride Na{sub 2}CaVO{sub 4}F prepared by solid-state synthesis using stoichiometric amounts of V{sub 2}O{sub 5}, CaCO{sub 3}, Na{sub 2}CO{sub 3} and NaF were characterized using high-resolution neutron powder diffraction. The structural changes between 25 °C and 750 °C revealed that the two structural subunits in this material behave different when heated: there is an expansion of the face-shared FNa{sub 4}Ca{sub 2} octahedra while the VO{sub 4} tetrahedra due to increased thermal disorder reveal marginal bond contractions. Bond valences and the global instability index point to significant structural disorder at 750 °C. - Graphical abstract: The structure of the novel oxyfluoride Na{sub 2}CaVO{sub 4}F is studied at room temperature and high-temperatures. The structure can be viewed as layers of compression and elongation of polyhedral subunits, which change as a function of temperature. - Highlights: • The novel oxyfluoride, Na{sub 2}CaVO{sub 4}F, is synthesized via solid-state method. • High-resolution neutron diffraction data is used to analyze the structure of Na{sub 2}CaVO{sub 4}F. • Structural subunits exhibit expansion and contraction with increasing temperature. • Higher temperatures increase instability within the structure of Na{sub 2}CaVO{sub 4}F.},
doi = {10.1016/J.JSSC.2017.03.027},
url = {https://www.osti.gov/biblio/22658297}, journal = {Journal of Solid State Chemistry},
issn = {0022-4596},
number = ,
volume = 250,
place = {United States},
year = {Thu Jun 15 00:00:00 EDT 2017},
month = {Thu Jun 15 00:00:00 EDT 2017}
}