Thermodynamic model of solid non-stoichiometric uranium dioxide

  • Yakub E
  • Ronchi C
  • Iosilevski I
  • 13

    Readers

    Mendeley users who have this article in their library.
  • 16

    Citations

    Citations of this article.

Abstract

A new equation of state for solid UO2+x is presented, based on an extended ionic model. A thermodynamic description of the imperfect and non-stoichiometric ionic solid is obtained accounting for short- and long-ranged inter-ionic forces, as well as for formation of Frenkel defects. Both Coulomb and short-range interactions between defects are encompassed in a highly non-ideal ionic system where interactions of Frenkel defects are taken into account explicitly as short-ranged interactions of quasi-dipoles. A simplified analytical form for the free energy of the perfect anharmonic crystal was obtained and then combined with additional contributions from formation and interaction of defects. By fitting a few numerical constants, the variations of thermodynamic properties of UO2+x are predicted as functions of temperature, density and stoichiometry. The model describes the pre-melting transition into the superionic state in solid stoichiometric UO2 and predicts the behaviour of the transition line in the non-stoichiometric domain.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free