Defect formation and water incorporation in Y2O3

The molecular statics method is used to study the formation of defects and water incorporation in Y2O3. The crystal structure, the isothermal compressibility, and the formation enthalpy of Y2O3 calculated with the chosen interaction potentials are in good agreement with the experimental data. The formation energies of intrinsic and impurity defects are evaluated. The binding energy of protons and oxygen vacancies with an acceptor impurity at different distances is calculated. Various water incorporation reactions in the oxide are examined, including the mechanisms involving oxygen interstitial sites and oxygen vacancies produced by the acceptor doping. It is shown that the water incorporation in pure Y2O3 is energetically less favorable than in the acceptor doped oxide. (C) 2011 Elsevier Ltd. All rights reserved.