Behavior of actinide dioxides under pressure: <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">U</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Th</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>

Idiri, M.; Bihan, T. Le; Heathman, S.; Rébizant, J.

doi:10.1103/physrevb.70.014113

Cited by 259 publications

(206 citation statements)

References 18 publications

Supporting

Mentioning

159

Contrasting

Order By: Relevance

“…The values of lattice parameter, bulk modulus, elastic constants and cohesive energy are given in [19,20] which is in good agreement with experiment and abinitio results [21][22][23][24][25]. Contrary to the previous MD results [11][12][13][14][15], in the present paper the lattice parameter is underestimated about 1.3% and 3% compared to the ab-initio calculations and experimental data, respectively [22,23].…”

Section: Resultscontrasting

confidence: 31%

Modeling Superionic Behavior of Plutonium Dioxide

Günay

Akgenc

Taşseven

2016

High Temperature Materials and Processes

View full text Add to dashboard Cite

The Bredig transition to the superionic phase indicated with the  -peak in p C was highly expected for 2 PuO as other actinide dioxides. However, least-square fit and local smoothing techniques applied to the experimental enthalpy data of plutonium dioxide in 80's could not detect a  -peak in specific heat that might be due to too scattered and insufficient experimental data. Therefore, this issue has not been yet put beyond the doubts. In the current article, a superionic model of 2 PuO is developed with partially ionic model of a rigid ion potential. Thermophysical properties were calculated in constant pressure-temperature ensemble using molecular dynamics simulation. The Bredig transition with vicinity of a  -peak in specific heat was a successfully observed for the model system at about 2100K.Moreover, the experimental enthalpy change was well reproduced before and after the estimated transition temperature.

show abstract

Section: Resultscontrasting

confidence: 31%

Modeling Superionic Behavior of Plutonium Dioxide

Günay

Akgenc

Taşseven

2016

High Temperature Materials and Processes

View full text Add to dashboard Cite

show abstract

“…An experiment showed the pressureinduced phase transition from fluorite to cotunnite phase starts at ∼42 GPa [30], whereas a first-principles calculated setout pressure is about 38 GPa [31]. Local pressure due to irradiation effects is usually higher than this threshold value and the excess energy transferred from irradiation tracks to lattice can overcome the possible barrier easily.…”

Section: Resultsmentioning

confidence: 99%

Molecular dynamics study on planar clustering of xenon in UO2

Geng¹,

Chen²,

Kaneta³

et al. 2008

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Interatomic potentials of uranium dioxide are investigated on their applicability to model structural stabilities beyond fluorite phase by comparing with ab-initio results. A high pressure cotunnite phase and loosely stacking virtual crystal are involved in order to get a primary confidence for large-scale deformation modelings of UO 2 under irradiation damages. The behavior of Xe atoms in UO 2 fuel is studied with molecular dynamics simulations. Besides the ground state bubble geometry, we find that a planar distribution is also (meta-)stable for xenon under thermodynamic perturbations. The Xe atoms with a planar configuration are in a liquid state at a typical reactor temperature of 1000 K, which presents a modulated layer-structure near the interface with solid UO 2 . A planar defects loop remains after these Xe atoms are released out.

show abstract

“…The calculated equilibrium properties are listed in Table 1, as well as the available values from experiments 20) and other calculations 21,22) for comparison. A good agreement among these data can be found.…”

Section: Structural Properties Of Pure Uomentioning

confidence: 99%

First-Principles Calculation of Point Defects in Uranium Dioxide

et al. 2006

View full text Add to dashboard Cite

A first-principles calculation for uranium dioxide (UO 2 ) in an antiferromagnetic structure with four types of point defects, uranium vacancy, oxygen vacancy, uranium interstitial, and oxygen interstitial, has been performed by the projector-augmented-wave method with generalized gradient approximation combined with the Hubbard U correction. Defect formation energies are estimated under lattice relaxation for supercells containing 1, 2, and 8 unit cells of UO 2 . The electronic structure, the atomic displacement and the stability of defected systems are obtained, and the effects of cell sizes on these properties are discussed. The results form a self-consistent dataset of formation energies and atomic distance variations of various point defects in UO 2 with relatively high precision. We show that a supercell with 8 UO 2 unit cells or larger is necessary to investigate the defect behavior with reliable precision, since point defects have a wide-ranging effect, not only on the first nearest neighbor atoms of the defect, but on the second neighbors and on more distant atoms.

show abstract

Behavior of actinide dioxides under pressure: UO2andThO2

Cited by 259 publications

References 18 publications

Modeling Superionic Behavior of Plutonium Dioxide

Modeling Superionic Behavior of Plutonium Dioxide

Molecular dynamics study on planar clustering of xenon in UO2

First-Principles Calculation of Point Defects in Uranium Dioxide

Contact Info

Product

Resources

About