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Related papers: Structural behavior of uranium dioxide under press…

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A comprehensive investigation on point defects and their clustering behavior in nonstoichiometric uranium dioxide UO2+x is carried out using LSDA+U method based on density functional theory. Accurate energetic information and charge…

Materials Science · Physics 2009-11-13 Hua Y. Geng , Ying Chen , Yasunori Kaneta , Misako Iwasawa , Toshiharu Ohnuma , Motoyasu Kinoshita

Structural changes in REMnO3 (RE= Y, Ho, Lu) under high pressure were examined by synchrotron x-ray diffraction methods at room temperature. Compression occurs more readily in the ab plane than along the c-axis. Under hydrostatic pressure…

Materials Science · Physics 2015-05-20 P. Gao , Z. Chen , T. A. Tyson , T. Wu , K. H. Ahn , Z. Liu , R. Tappero , S. B. Kim , S. -W. Cheong

Under pressure many rare earths and actinide metals transform to a-U structure or its lower symmetry distorted forms. We have reinterpreted the diffraction data of Dabos et al for Pu (reference 4) and find that a Am IV type distorted a-U…

Materials Science · Physics 2009-11-10 S. K. Sikka

Uranium manganese germanide, UMn2Ge2, crystallizes in body-centered tetragonal ThCr2Si2 structure with space group I4/mmm, a = 3.993A and c = 10.809A under ambient conditions. Energy dispersive X-ray diffraction was used to study the…

Materials Science · Physics 2009-11-10 Vasudeva Siruguri , S. K. Paranjpe , P. Raj , A. Sathyamoorthy , Jean Paul Itie , Alain Polian

The equation of state, structural behavior and phase stability of {\alpha}-uranium have been investigated up to 1.3 TPa using density functional theory, adopting a simple description of electronic structure that neglects the spin-orbit…

Materials Science · Physics 2015-05-28 S. Adak , H. Nakotte , P. F. de Châtel , B. Kiefer

In pursue of a systematic characterization of rare-earth vanadates under compression, in this work we present a multifaceted study of the phase behavior of zircon-type orthovanadate PrVO$_4$ under high pressure conditions, up until 24 GPa.…

The structural properties of LaRu$_2$P$_2$ under external pressure have been studied up to 14 GPa, employing high-energy x-ray diffraction in a diamond-anvil pressure cell. At ambient conditions, LaRu$_2$P$_2$ (I4/mmm) has a tetragonal…

We have investigated structural and magnetic phase transitions under high pressures in a quaternary rare earth transition metal arsenide oxide NdCoAsO compound that is isostructural to high temperature superconductor NdFeAsO. Four-probe…

The superconducting pyrochlore oxide Cd2Re2O7 (Tc = 1 K), which is now considered as a candidate of the spin-orbit-coupled metal, shows an inversion-symmetry-breaking structural transition at Ts1 = 200 K. Ts1 decreases with increasing…

Strongly Correlated Electrons · Physics 2018-04-30 Yasuhito Matsubayashi , Takumi Hasegawa , Norio Ogita , Jun-ichi Yamaura , Zenji Hiroi

By employing first-principles metadynamics simulations, we explore the 300 K structures of solid hydrogen over the pressure range 150-300 GPa. At 200 GPa, we find the ambient-pressure disordered hexagonal close-packed (hcp) phase transited…

Materials Science · Physics 2012-08-16 Hanyu Liu , Li Zhu , Wenwen Cui , Yanming Ma

A potential orthorhombic phase of Ta$_2$O$_5$, designated as Y-Ta$_2$O$_5$, is predicted under high-pressure conditions through density functional theory (DFT) calculations combined with structural search algorithms. This phase, consisting…

Materials Science · Physics 2025-07-22 Yan Gong , HuiMin Tang , Yong Yang , Yoshiyuki Kawazoe

Formation Gibbs free energy of point defects and oxygen clusters in uranium dioxide at high-pressure high-temperature conditions are calculated from first principles, using the LSDA+U approach for the electronic structure and the Debye…

Materials Science · Physics 2011-12-21 Hua Y. Geng , Hong X. Song , K. Jin , S. K. Xiang , Q. Wu

The crystalline structures of lanthanum tetraboride, LaB4, under pressure are investigated using a genetic algorithm method coupled with first-principles calculations. We find two low-enthalpy phases for LaB4 as the thermodynamic ground…

Materials Science · Physics 2022-03-14 Chen Pan , Sheng-Yan Wang , Hui Tang , Hong-Yun Wu , Hong Jiang , Yue-Hua Su , Chao Zhang

We study the electronic structure of cubic phase uranium dioxide at different volumes using a combination of density functional theory and dynamical mean-field theory. The \emph{ab initio} calculations predict an orbital-selective Mott…

Strongly Correlated Electrons · Physics 2017-11-22 Li Huang , Yilin Wang , Philipp Werner

The charge transfer antiferromagnetic (T$_{N}$ =220 K) insulator EuNiO$_{3}$ undergoes, at ambient pressure, a temperature-induced metal insulator MI transition at T$_{MI}$=463 K. We have investigated the effect of pressure (up to p~20 GPa)…

Strongly Correlated Electrons · Physics 2009-11-11 R. Lengsdorf , A. Barla , J. A. Alonso , M. J. Martinez-Lope , H. Micklitz , M. M. Abd-Elmeguid

The structural properties of Thallium (III) oxide (Tl2O3) have been studied both experimentally and theoretically under compression at room temperature. X-ray powder diffraction measurements up to 37.7 GPa have been complemented with ab…

We study compression of coesite to pressures above 35 GPa, substantially beyond the equilibrium transition pressure to octahedral phases (8 GPa to stishovite). Experiments at room temperature showed that up to 30 GPa the metastable coesite…

Materials Science · Physics 2025-09-22 David Vrba , Roman Martoňák

We report direct experimental evidence of antiferroelectric to paraelectric phase transition under pressure in NaNbO3 using neutron diffraction at room temperature. The paraelectric phase is found to stabilize above 8 GPa and its crystal…

Materials Science · Physics 2015-06-11 S. K. Mishra , M. K. Gupta , R. Mittal , S. L. Chaplot , Thomas Hansen

Iron sesquioxide (Fe2O3) displays pressure and temperature induced spin and structural transitions. Our calculations show that, density functional theory (DFT), in the generalized gradient approximation (GGA) scheme, is capable of capturing…

Materials Science · Physics 2009-05-22 Dipta Bhanu Ghosh , Stefano de Gironcoli

The high pressure structural properties of bismuth oxide Bi2SiO5 have been investigated up to 28 GPa using in situ powder synchrotron X-ray diffraction and up to 50 GPa with DFT calculations. The monoclinic structure is found to persist up…