Y. Iwano, A DEFECT STRUCTURE STUDY OF NONSTOICHIOMETRIC URANIUM-DIOXIDE BY STATISTICAL-MECHANICAL MODELS, Journal of nuclear materials, 209(1), 1994, pp. 79-91
In order to clarify the defect structure of UO2+x, two types of defect
clusters, the 2:2:2 cluster and the cuboctahedral cluster, are explor
ed by comparing the oxygen potential and the partial molar enthalpy of
oxygen calculated from the statistical-mechanical model formulated fo
r each cluster with the measured ones. The model for the cuboctahedral
clusters in equilibrium between various charge states gives good agre
ements with both the oxygen potential and the partial molar enthalpy o
f oxygen, whereas the models of the clusters which assume a single cha
rge state do not.