Thermodynamic reassessment of U–Gd–O system

Thermodynamic modelling of the general NiAs-type structure: A study of first principle energies of formation for binary Ni-containing B8 compounds

“…Refs. [8][9][10][11], it is now state of the art to combine first principle calculations with experiments to develop physically meaningful thermodynamic models.…”

Thermodynamic assessment of the U–Y–O system

“…Since there is a significant difference between the proposed phase regions, and Aitken and Joseph [7] only determined the presence of the fluorite and rhombohedral phases, the phase equilibria of Bartram et al [6] were used in the current assessment. A limitation in the work of Bartram et al [6] however, is that no three-phase regions appear in their proposed diagram, whereas that would be expected based on observations in similar systems containing rare earths (RE) [8]. The only other thermodynamic data for this system are from thermogravimetric determinations of oxygen potential vs O/M of Hagemark and Broli [9] and partial pressure determinations of U, UO, and UO 2 species from the Knudsen effusion mass spectrometry (KEMS) of Nakajima et al [10].…”

“…Nakajima et al [10] do report significant fragmentation of UO 2 in the KEMS measurements which may explain their high values for U and UO vapor species. [8,18,20,21]. These include the extensive fluorite solid solution region and the emergence of at least one rhombohedral phase at the higher yttrium or RE concentrations.…”

Synthesis of UO2 and ThO2 doped with Gd2O3

“…phase behavior, thermal expansion and thermal conductivity) of Gd 2 O 3 -doped UO 2 [4,3] and references therein. Also recently, research is still being performed in this field [5][6][7][8]. Fundamental studies on doped UO 2 are of interest to get more insights in the stability of the uranium crystal lattice when foreign elements are accommodated into its crystal structure and also to investigate the behavior and coordination chemistry of such foreign elements in the UO 2 matrix.…”