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Abstract

Crystal uranium dioxide is known to be of ionic structure. Liquid uranium dioxide is presumed to keep a significant part of ionic bonding on melting. It is well known that an adequate description of ionic systems both in simplified models and in real ionic liquids is only obtained when bound associations are taken into account explicitly. A study of thermodynamic properties of liquid uranium dioxide has dealt with the assumption that liquid UO(2) may be successfully studied in the frame of several, potentially equivalent, models, including the quasi-molecular model as well as the pure ionic one. For two of such simplified ionic models calculations were performed which clearly demonstrate their merits and limits. The restricted ionic model (RIM-4:2) was considered first (ie representing an electrically neutral stoichiometric compound of two ionic species of type (U(4+)) and (O(2-)), with both ions having equal hard-sphere diameters). In the context of the restricted primitive ionic model (RPM) a mixture of ions subjected to merely Coulomb interactions was studied. Furthermore, an additional short-range attractive interaction of van der Waals' type was taken into account within the improved restricted ionic model (IRIM).

Additional information

Authors: GRYAZNOV V K, Institute of Chemical Physics at Chernogolovka (RU);FORTOV V E, Institute of Chemical Physics at Chernogolovka (RU);IOSILEVSKI I L, Moscow Institute of Physics and Technology (RU);YAKUB E S, Odessa State Medical University (UA);HYLAND G J, University of Warwick, Coventry (GB);RONCHI C, JRC Karlsruhe (DE)
Bibliographic Reference: Paper presented: International Conference on Weak Interacting Plasma, Boston (US), 25-28 August 1998
Availability: Available from (1) as Paper EN 41399 ORA
Record Number: 199810786 / Last updated on: 1998-07-02
Category: PUBLICATION
Original language: en
Available languages: en