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Related papers: Structural Analysis of Amorphous GeO$_2$ under Hig…

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We report experimental evidence for pressure instabilities in the model multiferroic BiFeO3 and namely reveal two structural phase transitions around 3 GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a synchrotron…

Materials Science · Physics 2011-07-26 R. Haumont , P. Bouvier , A. Pashkin , K. Rabia , S. Frank , B. Dkhil , W. A. Crichton , C. A. Kuntscher , J. Kreisel

The discrete Gaussian model for the surface of a crystal deposited on a disordered substrate is studied by Monte Carlo simulations. A continuous transition is found from a phase with a thermally-induced roughness to a glassy one in which…

Condensed Matter · Physics 2009-10-22 D. Cule , Y. Shapir

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

We discuss an inverse approach for atomistic modeling of glassy materials. The focus is on structural modeling and electronic properties of hydrogenated amorphous silicon and glassy GeSe2 alloy. The work is based upon a new approach…

Disordered Systems and Neural Networks · Physics 2009-11-13 Parthapratim Biswas , D. A. Drabold

The atomic-level structure of bulk metallic glasses is a key determinant of their properties. An accurate representation of amorphous systems in computational studies has traditionally required large supercells that are unfortunately…

Materials Science · Physics 2024-01-17 Siya Zhu , Jan Schroers , Stefano Curtarolo , Hagen Eckert , Axel van de Walle

TiPO$_4$ shows interesting structural and magnetic properties as temperature and pressure are varied, such as a spin-Peierls phase transition and the development of incommensurate modulations of the lattice. Recently, high pressure…

Strongly Correlated Electrons · Physics 2019-06-26 H. Johan M. Jönsson , Marcus Ekholm , Maxim Bykov , Leonid Dubrovinsky , Sander van Smaalen , Igor A. Abrikosov

We investigate the large-scale structure of amorphous ices and transitions between their different forms by quantifying their large-scale density fluctuations. Specifically, we simulate the isothermal compression of low-density amorphous…

Statistical Mechanics · Physics 2017-10-04 Fausto Martelli , Salvatore Torquato , Nicolas Giovambattista , Roberto Car

X-ray diffraction (XRD) experiments have been carried out on quartz-like GaPO4 at high pressure and room temperature. A transition to a high pressure disordered crystalline form occurs at 13.5 GPa. Slight heating using a YAG infrared laser…

Condensed Matter · Physics 2009-10-31 James Badro , Jean-Paul Itie , Alain Polian

The structural parameters of $\epsilon$-FeGe have been determined at ambient conditions using single crystal refinement. Powder diffraction have been carried out to determine structural properties and compressibility for pressures up to 30…

Strongly Correlated Electrons · Physics 2009-11-13 H. Wilhelm , M. Schmidt , R. Cardoso-Gil , U. Burkhardt , M. Hanfland , U. Schwarz , L. Akselrud

Determining atomistic structures from characterization data is one of the most common yet intricate problems in materials science. Particularly in amorphous materials, proposing structures that balance realism and agreement with experiments…

Disordered Systems and Neural Networks · Physics 2026-03-25 Jiawei Guo , Daniel Schwalbe-Koda

The temperature dependence of the non-ergodicity factor of vitreous GeO$_2$, $f_{q}(T)$, as deduced from elastic and quasi-elastic neutron scattering experiments, is analyzed. The data are collected in a wide range of temperatures from the…

Disordered Systems and Neural Networks · Physics 2015-05-13 S. Caponi , M. Zanatta , A. Fontana , L. E. Bove , L. Orsingher , F. Natali , C. Petrillo , F. Sacchetti

An ideal atomistic model of a disordered material should contradict no experiments,and should also be consistent with accurate force fields (either {\it ab initio}or empirical). We make significant progress toward jointly satisfying {\it…

Materials Science · Physics 2016-08-31 Parthapratim Biswas , De Nyago Tafen , D. A. Drabold

We present a study of the high-pressure behaviour Bi14WO24, a high oxide ion conductor member of the Bi2O3-WO3 binary system. The tetragonal polymorph of Bi14WO24 was studied under high-pressure conditions using synchrotron powder X-ray…

We study the structural evolution of Sr$_3$Ir$_2$O$_7$ as a function of pressure using x-ray diffraction. At a pressure of 54 GPa at room temperature, we observe a first-order structural phase transition, associated with a change from…

In this work we present an extensive study of glassy GeO$_2$ under laser induced dynamic compression. New VISAR and SOP data provide the extension of Hugoniot EoS up to the TPa range for this material including temperature measurements.…

We have characterized the high-pressure behavior of alpha-SnWO4. The compound has been studied up to 30 GPa using a diamond-anvil cell and synchrotron powder X-ray diffraction. We report evidence of two structural phase transitions in the…

The structure of La$_{1-x}$Ca$_{x}$MnO$_{3}$ solid solutions (x=0, 0.25, 0.50, 0.67, 1) under high pressure (up to 40-45 GPa) has been investigated by synchrotron X-ray powder diffraction (XRD) in order to characterize their volume…

Strongly Correlated Electrons · Physics 2007-05-23 A. Sani , C. Meneghini , S. Mobilio , Sugata Ray , D. D. Sarma , J. A. Alonso

Compared to the widely investigated crystalline polymorphs of gallium oxide (Ga2O3), knowledge about its amorphous state is still limited. With the help of a machine-learning interatomic potential, we conducted large-scale atomistic…

Materials Science · Physics 2024-04-29 Jiahui Zhang , Junlei Zhao , Jesper Byggmästar , Erkka J. Frankberg , Antti Kuronen

In the present work, we report a detailed density functional theory calculation on polymorphic InVO$_4$ phases by means of projector augmented wave method. The computed first-order structural phase transformation from orthorhombic…

Materials Science · Physics 2016-03-02 S. Mondal , S. Appalakondaiah , G. Vaitheeswaran

The crystal structure of the layered, perovskite-related LaTiO_3.41 (La_5Ti_5O_{17+\delta}) has been studied by synchrotron powder x-ray diffraction under hydrostatic pressure up to 27 GPa (T = 295 K). The ambient-pressure phase was found…

Strongly Correlated Electrons · Physics 2007-05-23 I. Loa , K. Syassen , X. Wang , F. Lichtenberg , M. Hanfland , C. A. Kuntscher