Equation of state of uranium dioxide : data collection The monograph deals with the thermodynamic properties of fluid uranium dioxide one of the most investigated materials of the last century up to its critical point. It presents an exhaustive theoretical introduction to quasi chemical models of liquids as well as their behaviour under non congruent vaporisation conditions. Particular emphasis is given to the properties of pure Coulombic systems and to the pseudoparticle approach which enables the partition function to be expressed in a simple but physically rigorous formulation. The construction of the equation of state of stoichiometric and non stoichiometric uranium dioxide is described in distinct steps from a critical assessment of the theoretical fundamentals to a thorough review of the pertinent thermochemical and thermophysical data. Calculations of the thermodynamic properties of UO2+x are performed for temperatures up to 11 000 K both for the condensed and gas phase. More than one hundred tables are collected in the Appendix containing all relevant thermodynamic data