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Related papers: Ab Initio Simulations of Hot, Dense Methane During…

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Methane is thought to have been an important greenhouse gas during the Archean, although its potential warming has been found to be limited at high concentrations due to its high shortwave absorption. We use the Met Office Unified Model, a…

The equation of state and the shock Hugoniot of deuterium are calculated using a first-principles approach, for the conditions of the recent shock experiments. We use density functional theory within a classical mapping of the quantum…

Strongly Correlated Electrons · Physics 2017-03-22 M. W. C. Dharma-wardana , Francois Perrot

Molecular dynamics (MD) simulation is applied to the condensation process of supersaturated vapors of methane, ethane, and carbon dioxide. Simulations of systems with up to a million particles were conducted with a massively parallel MD…

Recent high-dispersion spectroscopy from ground-based telescopes and high-precision spectroscopy from space observatories have enabled atmospheric observations of substellar objects, such as brown dwarfs and hot gaseous exoplanets, with…

Earth and Planetary Astrophysics · Physics 2025-03-31 Ko Hosokawa , Takayuki Kotani , Hajime Kawahara , Yui Kawashima , Kento Masuda , Aoi Takahashi , Kazuo Yoshioka

The principal Hugoniot for liquid hydrogen was obtained up to 55 GPa under laser-driven shock loading. Pressure and density of compressed hydrogen were determined by impedance-matching to a quartz standard. The shock temperature was…

We present equation of state data of shock compressed hydrogen and deuterium. These have been calculated in the physical picture by using {\it ab initio} molecular dynamics simulations based on finite temperature density functional theory…

The insulator-metal transition in hydrogen is one of the most outstanding problems in condensed matter physics. The high-pressure metallic phase is now predicted to be liquid atomic from T=0 K to very high temperatures. We have conducted…

Materials Science · Physics 2016-04-20 Mohamed Zaghoo , Ashkan Salamat , Isaac F. Silvera

We have performed quantum molecular dynamics simulations for dense helium to study the nonmetal-to-metal transition at high pressures. We present new results for the equation of state and the Hugoniot curve in the warm dense matter region.…

The phase diagram of oxygen is investigated for pressures from 50 to 130~GPa and temperatures up 1200 K using first principles theory. A metallic molecular structure with the $P6_3/mmc$ symmetry ($\eta^{'}$ phase) is determined to be…

Computational Physics · Physics 2019-02-19 S. F. Elatresh , S. A. Bonev

We report new results on the liquid to solid phase transition of benzene. We determine experimentally and investigate the properties of a number of parameters of the benzene metastable state under different pressures (from 0.1 up to 2200…

Chemical Physics · Physics 2019-08-06 Mustapha Azreg-Aïnou , Beycan İbrahimoǧlu

Using path integral Monte Carlo and density functional molecular dynamics (DFT-MD) simulations, we study the properties of MgSiO$_3$ enstatite in the regime of warm dense matter. We generate a consistent equation of state (EOS) that spans…

Materials Science · Physics 2020-12-02 Felipe González-Cataldo , Burkhard Militzer

We present extensive molecular dynamics (MD) simulations investigating numerous candidate crystal structures for hydrogen in conditions around the present experimental frontier (400GPa). Spontaneous phase transitions in the simulations…

Materials Science · Physics 2015-11-18 Ioan B. Magdau , Graeme J. Ackland

Superconductivity in the recently proposed ground-state structures of atomic metallic hydrogen is investigated over the pressure range 500 GPa to 3.5 TPa. Near molecular dissociation, the electron--phonon coupling $\lambda$ and renormalized…

Superconductivity · Physics 2015-05-28 Jeffrey M. McMahon , David M. Ceperley

Fermionic path integral Monte Carlo simulations have been applied to study the equilibrium properties of the hydrogen and deuterium in the density and temperature range of 1.6 < rs < 14.0 and 5000K < T < 167000K. We use this technique to…

Plasma Physics · Physics 2015-06-26 Burkhard Militzer , William Magro , David Ceperley

We have studied dense hydrogen and deuterium experimentally up to 320 GPa and using ab initio molecular dynamic (MD) simulations up to 370 GPa between 250 and 300 K. Raman and optical absorption spectra show significant anharmonic and…

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

Experimental results for the reflection coefficient of shock-compressed dense Xenon plasmas at pressures of 1.6 - 17 GPa and temperatures around 30 000 K using a laser beam with \lambda = 1.06 10^-6 m are compared with calculations based on…

Plasma Physics · Physics 2009-11-07 H. Reinholz , G. Roepke , A. Wierling , V. Mintsev , V. Gryaznov

Near 20.48K and in the temperature range 60--70K, anomalous behavior of thermodynamic, spectral, plastic, elastic and other properties of solid methane is observed. The anomalies in the vicinity of 20.48K are due to the phase $\alpha-\beta$…

Materials Science · Physics 2017-09-12 A. V. Leont'eva , A. Yu. Zakharov , A. Yu. Prokhorov

The static and dynamical properties of heavy water have been studied at ambient conditions with extensive Car-Parrinello molecular-dynamics simulations in the canonical ensemble, with temperatures ranging between 325 K and 400 K.…

Soft Condensed Matter · Physics 2007-05-23 P. H-L. Sit , Nicola Marzari

We introduce a novel method that combines the accuracy of Quantum Monte Carlo simulations with ab-initio Molecular Dynamics, in the spirit of Car-Parrinello. This method is then used for investigating the structure of a two-dimensional…

Computational Physics · Physics 2017-05-16 Francesco Calcavecchia , Thomas D. Kühne , Markus Holzmann