Abstract
In the present study, we investigated the thermodynamic properties of uranium dioxide (UO2) by molecular dynamics (MD) simulations. As for solid UO2, the lattice parameter, density, and enthalpy obtained by MD simulations were in good agreement with existing experimental data and previous theoretical predictions. The calculated thermal conductivities matched the experiment results at the midtemperature range but were underestimated at very low and very high temperatures. The calculation results of mean square displacement represented the stability of uranium at all temperatures and the high mobility of oxygen toward 3000 K. By fitting the diffusivity constant of oxygen with the Vogel-Fulcher-Tamman law, we noticed a secondary phase transition near 2006.4 K, which can be identified as a "strong" to "fragile" supercooled liquid or glass phase transition in UO 2. By fitting the oxygen diffusion constant with the Arrhenius equation, activation energies of 2.0 and 2.7 eV that we obtained were fairly close to the recommended values of 2.3 to 2.6 eV.
| Original language | English |
|---|---|
| Pages (from-to) | 360-369 |
| Number of pages | 10 |
| Journal | Nuclear Science and Engineering |
| Volume | 176 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1 Jan 2014 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Nuclear Energy and Engineering
Cite this
Molecular dynamics simulation of thermodynamic properties in uranium dioxide. / Wang, Xiangyu; Wu, Bin; Gao, Fei; Li, Xin; Sun, Xin; Khaleel, Mohammed A.; Akinlalu, Ademola V.; Liu, Li.
In: Nuclear Science and Engineering, Vol. 176, No. 3, 01.01.2014, p. 360-369.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Molecular dynamics simulation of thermodynamic properties in uranium dioxide
AU - Wang, Xiangyu
AU - Wu, Bin
AU - Gao, Fei
AU - Li, Xin
AU - Sun, Xin
AU - Khaleel, Mohammed A.
AU - Akinlalu, Ademola V.
AU - Liu, Li
PY - 2014/1/1
Y1 - 2014/1/1
N2 - In the present study, we investigated the thermodynamic properties of uranium dioxide (UO2) by molecular dynamics (MD) simulations. As for solid UO2, the lattice parameter, density, and enthalpy obtained by MD simulations were in good agreement with existing experimental data and previous theoretical predictions. The calculated thermal conductivities matched the experiment results at the midtemperature range but were underestimated at very low and very high temperatures. The calculation results of mean square displacement represented the stability of uranium at all temperatures and the high mobility of oxygen toward 3000 K. By fitting the diffusivity constant of oxygen with the Vogel-Fulcher-Tamman law, we noticed a secondary phase transition near 2006.4 K, which can be identified as a "strong" to "fragile" supercooled liquid or glass phase transition in UO 2. By fitting the oxygen diffusion constant with the Arrhenius equation, activation energies of 2.0 and 2.7 eV that we obtained were fairly close to the recommended values of 2.3 to 2.6 eV.
AB - In the present study, we investigated the thermodynamic properties of uranium dioxide (UO2) by molecular dynamics (MD) simulations. As for solid UO2, the lattice parameter, density, and enthalpy obtained by MD simulations were in good agreement with existing experimental data and previous theoretical predictions. The calculated thermal conductivities matched the experiment results at the midtemperature range but were underestimated at very low and very high temperatures. The calculation results of mean square displacement represented the stability of uranium at all temperatures and the high mobility of oxygen toward 3000 K. By fitting the diffusivity constant of oxygen with the Vogel-Fulcher-Tamman law, we noticed a secondary phase transition near 2006.4 K, which can be identified as a "strong" to "fragile" supercooled liquid or glass phase transition in UO 2. By fitting the oxygen diffusion constant with the Arrhenius equation, activation energies of 2.0 and 2.7 eV that we obtained were fairly close to the recommended values of 2.3 to 2.6 eV.
UR - http://www.scopus.com/inward/record.url?scp=84899668166&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84899668166&partnerID=8YFLogxK
U2 - 10.13182/NSE13-14
DO - 10.13182/NSE13-14
M3 - Article
AN - SCOPUS:84899668166
VL - 176
SP - 360
EP - 369
JO - Nuclear Science and Engineering
JF - Nuclear Science and Engineering
SN - 0029-5639
IS - 3
ER -