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Related papers: High-pressure isostructural transition in nitrogen

200 papers

Using ab initio evolutionary simulations, we predict the existence of five novel stable Li-N compounds at pressures from 0 to 100 GPa (Li13N, Li5N, Li3N2, LiN2, and LiN5). Structures of these compounds contain of isolated N ions, N2 dimers,…

Materials Science · Physics 2015-04-28 Yanqing Shen , Artem R. Oganov , Guangri Qian , Huafeng Dong , Qiang Zhu , Zhongxiang Zhou

We report the evolution of charge density wave states under pressure for two NbS3 phases triclinic (phase I) and monoclinic (phase II) at room temperature. Raman and X-ray diffraction (XRD) techniques are applied. The x-ray studies on the…

Metallization and dissociation are key transformations in diatomic molecules at high densities particularly significant for modeling giant planets. Using X-ray absorption spectroscopy and atomistic modeling, we demonstrate that in halogens,…

Ab initio molecular dynamic method within the framework of density functional theory is applied to analyze the structural and electronic properties of crystalline molecular hydrogen at temperature 100\,K. Pressure, pair correlation function…

Materials Science · Physics 2022-01-12 I. Saitov

The hydrogen phase diagram has a number of unusual features which are generally well reproduced by density functional calculations. Unfortunately, these calculations fail to provide good physical insights into why those features occur. In…

Materials Science · Physics 2020-10-28 Hongxiang Zong , Heather Wiebe , Graeme J. Ackland

Under pressure, metals exhibit increasingly shorter interatomic distances. Intuitively, this response is expected to be accompanied by an increase in the widths of the valence and conduction bands and hence a more pronounced…

Materials Science · Physics 2017-10-16 Y. Ma , M. I. Eremets , A. R. Oganov , Y. Xie , I. Trojan , S. Medvedev , A. O. Lyakhov , M. Valle , V. Prakapenka

Understanding the behavior of molecular systems under pressure is a fundamental problem in condensed matter physics. In the case of nitrogen, the determination of the phase diagram and in particular of the melting line, are largely open…

Materials Science · Physics 2010-07-27 Davide Donadio , Leonardo Spanu , Ivan Duchemin , Francois Gygi , Giulia Galli

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

The interplay between electron correlation and nuclear quantum effects makes our understanding of elemental hydrogen a formidable challenge. Here, we present the phase diagram of hydrogen and deuterium at low temperatures and high-pressure…

Materials Science · Physics 2023-06-28 Lorenzo Monacelli , Michele Casula , Kosuke Nakano , Sandro Sorella , Francesco Mauri

High-temperature and high-pressure experiments were conducted on columbite-type ZnNb2O6, reaching temperatures up to 873 K at ambient pressure and pressures up to 30 GPa at ambient temperature, respectively. Through systematic analysis…

Diatomic nitrogen is an archetypal molecular system known for its exceptional stability and complex behavior at high pressures and temperatures, including rich solid polymorphism, formation of energetic states, and an insulator-to-metal…

Structural changes of Li2C2 under pressure were studied by synchrotron x-ray diffraction in a diamond anvil cell under hydrostatic conditions and by using evolutionary search methodology for crystal structure prediction. We show that the…

We construct a fast, transferable, general purpose, machine-learning interatomic potential suitable for large-scale simulations of $N_2$. The potential is trained only on high quality quantum chemical molecule-molecule interactions, no…

Computational Physics · Physics 2024-05-10 Marcin Kirsz , Ciprian G. Pruteanu , Peter I. C. Cooke , Graeme J. Ackland

Electronic properties of silicon-based clathrates can be tuned by boron incorporation into the silicon cage network. Sodium borosilicides clathrate outstands with uncommon stoichiometry and expected metallic properties, in contrast to other…

Transition of molecular hydrogen to atomic ionized state with increase of temperature and pressure poses still unresolved problems for experimental methods and theory. Here we analyze the dynamics of this transition and show its…

Materials Science · Physics 2020-03-25 Ilya D. Fedorov , Nikita D. Orekhov , Vladimir V. Stegailov

LaNiGa2 is a time-reversal symmetry breaking superconductor with symmetry protected band crossings, making it an ideal platform for investigating the interplay between unconventional superconductivity and electronic structure topology. Here…

High pressure x-ray diffraction up to 30 GPa and resonant emission x-ray spectroscopy and partial fluorescence yield x-ray absorption spectroscopy up to 52 GPa were used to study how the structural and electronic properties of UTe$_2$…

We report the results of the X-ray diffraction study of B2O3 glass in the pressure interval up to 10 GPa in the 300-700 K temperature range, the results of in-situ volumetric measurements of the glass at pressures up to 9 GPa at room…

Disordered Systems and Neural Networks · Physics 2008-07-19 V. V. Brazhkin , Y. Katayama , K. Trachenko , O. B. Tsiok , A. G. Lyapin , Emilio Artacho , M. Dove , G. Ferlat , Y. Inamura , H. Saitoh

We map the high-pressure phase diagram of nitrogen hydrate up to 16 GPa at room temperature by combining neutron diffraction, Raman spectroscopy, and crystal structure prediction. We reveal a rich sequence of structural transformations,…

Liquid atomic metallic hydrogen is the simplest, lightest, and most abundant of all liquid metals. The role of nucleon motions or ion dynamics has been somewhat ignored in relation to the dissociative insulator-metal transition. Almost all…

Other Condensed Matter · Physics 2018-09-12 Mohamed Zaghoo , Rachel Husband , Isaac F. Silvera