Activation volumes of oxygen self-diffusion in fluorite structured oxides

Christopoulos, S-R G.; Kordatos, A.; Cooper, Michael William D.; Fitzpatrick, M. E.; Chroneos, A.

doi:10.1088/2053-1591/3/10/105504

Title: Activation volumes of oxygen self-diffusion in fluorite structured oxides

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Abstract

In this study, fluorite structured oxides are used in numerous applications and as such it is necessary to determine their materials properties over a range of conditions. In the present study we employ molecular dynamics calculations to calculate the elastic and expansivity data, which are then used in a thermodynamic model (the cBΩ model) to calculate the activation volumes of oxygen self-diffusion coefficient in ThO₂, UO₂ and PuO₂ fluorite structured oxides over a wide temperature range. We present relations to calculate the activation volumes of oxygen self-diffusion coefficient in ThO₂, UO₂ and PuO₂ for a wide range of temperature (300–1700 K) and pressure (–7.5 to 7.5 GPa).

Authors:

Christopoulos, S-R G. ^[1]; Kordatos, A. ^[1]; Cooper, Michael William D. ^[2]; Fitzpatrick, M. E. ^[1]; Chroneos, A. ^[1]

Coventry Univ., Coventry (United Kingdom)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: Thu Oct 27 00:00:00 EDT 2016

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Office of Nuclear Energy (NE)

OSTI Identifier:: 1331276

Report Number(s):: LA-UR-16-21486
Journal ID: ISSN 2053-1591

Grant/Contract Number:: AC52-06NA25396

Resource Type:: Accepted Manuscript

Journal Name:: Materials Research Express (Online)

Additional Journal Information:: Journal Name: Materials Research Express (Online); Journal Volume: 3; Journal Issue: 10; Journal ID: ISSN 2053-1591

Publisher:: IOP Publishing

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Christopoulos, S-R G., Kordatos, A., Cooper, Michael William D., Fitzpatrick, M. E., and Chroneos, A. Activation volumes of oxygen self-diffusion in fluorite structured oxides.  United States: N. p., 2016. 
Web.  doi:10.1088/2053-1591/3/10/105504.

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                    Christopoulos, S-R G., Kordatos, A., Cooper, Michael William D., Fitzpatrick, M. E., & Chroneos, A. Activation volumes of oxygen self-diffusion in fluorite structured oxides.  United States.  https://doi.org/10.1088/2053-1591/3/10/105504

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                    Christopoulos, S-R G., Kordatos, A., Cooper, Michael William D., Fitzpatrick, M. E., and Chroneos, A. Thu .  
"Activation volumes of oxygen self-diffusion in fluorite structured oxides".  United States.  https://doi.org/10.1088/2053-1591/3/10/105504.  https://www.osti.gov/servlets/purl/1331276.

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@article{osti_1331276,

  title        = {Activation volumes of oxygen self-diffusion in fluorite structured oxides},

  author       = {Christopoulos, S-R G. and Kordatos, A. and Cooper, Michael William D. and Fitzpatrick, M. E. and Chroneos, A.},

  abstractNote = {In this study, fluorite structured oxides are used in numerous applications and as such it is necessary to determine their materials properties over a range of conditions. In the present study we employ molecular dynamics calculations to calculate the elastic and expansivity data, which are then used in a thermodynamic model (the cBΩ model) to calculate the activation volumes of oxygen self-diffusion coefficient in ThO2, UO2 and PuO2 fluorite structured oxides over a wide temperature range. We present relations to calculate the activation volumes of oxygen self-diffusion coefficient in ThO2, UO2 and PuO2 for a wide range of temperature (300–1700 K) and pressure (–7.5 to 7.5 GPa).},

  doi          = {10.1088/2053-1591/3/10/105504},

  journal      = {Materials Research Express (Online)},

  number       = 10,

  volume       = 3,

  place        = {United States},

  year         = {Thu Oct 27 00:00:00 EDT 2016},

  month        = {Thu Oct 27 00:00:00 EDT 2016}

}

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