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Structural Phase Transition of ThC Under High Pressure.

ABSTRACT: Thorium monocarbide (ThC) as a potential fuel for next generation nuclear reactor has been subjected to its structural stability investigation under high pressure, and so far no one reported the observation of structure phase transition induced by pressure. Here, utilizing the synchrotron X-ray diffraction technique, we for the first time, experimentally revealed the phase transition of ThC from B1 to P4/nmm at pressure of ~58?GPa at ambient temperature. A volume collapse of 10.2% was estimated during the phase transition. A modulus of 147?GPa for ThC at ambient pressure was obtained and the stoichiometry was attributed to the discrepancy of this value to the previous reports.

SUBMITTER: Yu C

PROVIDER: S-EPMC5428025 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Structural Phase Transition of ThC Under High Pressure.

Yu Cun C Lin Jun J Huai Ping P Guo Yongliang Y Ke Xuezhi X Yu Xiaohe X Yang Ke K Li Nana N Yang Wenge W Sun Baoxing B Xie Ruobing R Xu Hongjie H

Scientific reports 20170307 1

Thorium monocarbide (ThC) as a potential fuel for next generation nuclear reactor has been subjected to its structural stability investigation under high pressure, and so far no one reported the observation of structure phase transition induced by pressure. Here, utilizing the synchrotron X-ray diffraction technique, we for the first time, experimentally revealed the phase transition of ThC from B1 to P4/nmm at pressure of ~58 GPa at ambient temperature. A volume collapse of 10.2% was estimated ...[more]

PMID: 28273889

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