English
Related papers

Related papers: Molecular Dissociation in Hot, Dense Hydrogen

200 papers

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 study the effect of temperature up to 1000K on the structure of dense molecular para-hydrogen and ortho-deuterium, using the path-integral Monte Carlo method. We find a structural phase transition from orientationally disordered…

Materials Science · Physics 2009-11-07 T. Cui , Y. Takada , Q. Cui , Y. Ma , G. Zou

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

We present a simplified chemical and thermal model designed to allow computationally efficient study of the thermal evolution of metal-poor gas within large numerical simulations. Our main simplification is the neglect of the molecular…

Astrophysics · Physics 2009-06-23 S. C. O. Glover , A. -K. Jappsen

Young massive stars produce Far-UV photons which dissociate the molecular gas on the surfaces of their parent molecular clouds. Of the many dissociation products which result from this ``back-reaction'', atomic hydrogen \HI is one of the…

Astrophysics · Physics 2016-01-27 Ronald J. Allen

Using two first-principles computer simulation techniques, path integral Monte-Carlo and density functional theory molecular dynamics, we derive the equation of state of magnesium in the regime of warm dense matter, with densities ranging…

Materials Science · Physics 2020-08-20 Felipe González-Cataldo , François Soubiran , Burkhard Militzer

Two first-principles simulation techniques, path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD), are applied to study hot, dense helium in the density-temperature range of 0.387 - 5.35 g/cc and 500 K -…

Materials Science · Physics 2015-05-13 B. Militzer

We derive radial and vertical distributions of HI and H2 gas densities in our Galaxy by using the terminal velocity method. We calculate the molecular fraction (f_mol) defined as the ratio of the molecular hydrogen to total hydrogen gas…

Astrophysics · Physics 2007-05-23 K. Imamura , Y. Sofue

Liquid metallic hydrogen (LMH) was recently produced under static compression and high temperatures in bench-top experiments. Here, we report a study of the optical reflectance of LMH in the pressure region of 1.4-1.7 Mbar and use the Drude…

Materials Science · Physics 2022-06-01 Mohamed Zaghoo , Isaac F. Silvera

We present results of molecular dynamics simulations of the electron system on the surface of liquid helium. The simulations are done for 1600 electrons with periodic boundary conditions. Electron scattering by capillary waves and phonons…

Mesoscale and Nanoscale Physics · Physics 2018-09-03 K. Moskovtsev amd M. I. Dykman

We present the detection analysis of a diffuse molecular cloud at z$_{abs}$=2.4636 towards the quasar SDSS J1513+0352(z$_{em}\,\simeq$ 2.68) observed with the X-shooter spectrograph(VLT). We measure very high column densities of atomic and…

Observations of spiral galaxies show a strong linear correlation between the ratio of molecular to atomic hydrogen surface density R_mol and midplane pressure. To explain this, we simulate three-dimensional, magnetized turbulence, including…

Astrophysics of Galaxies · Physics 2015-05-20 Mordecai-Mark Mac Low , Simon C. O. Glover

Using the pseudopotential density functional method as well as equilibrium thermodynamic functions, we explore the process of releasing H2 molecules adsorbed on a transition metal atom caused by the hydrogen-ammonia partial pressure…

Materials Science · Physics 2015-05-19 Hoonkyung Lee , Bing Huang , Wenhui Duan , Jisoon Ihm

The presence of small amounts of atomic hydrogen, detected as absorption dips in the 21 cm line spectrum, is a well-known characteristic of dark clouds. The abundance of hydrogen atoms measured in the densest regions of molecular clouds can…

Astrophysics of Galaxies · Physics 2018-11-21 Marco Padovani , Daniele Galli , Alexei V. Ivlev , Paola Caselli , Andrea Ferrara

In this work, we determine the dissociation temperature of the hydrogen (H$_2$) hydrate by computer simulation using two different methods. In both cases, the molecules of water and H$_2$ are modeled using the TIP4P/Ice and a modified…

Soft Condensed Matter · Physics 2026-01-27 Miguel J. Torrejon , S. Blazquez , Jesus Algaba , M. M. Conde , F. J. Blas

We present deep spectroscopic (3600 - 24700 A) X-shooter observations of the bright Herbig-Haro object HH1, one of the best laboratories to study the chemical and physical modifications caused by protostellar shocks on the natal cloud. We…

Solar and Stellar Astrophysics · Physics 2015-10-26 T. Giannini , S. Antoniucci , B. Nisini , F. Bacciotti , L. Podio

Microgels are soft colloidal particles that, when dispersed in a solvent, swell and deswell in response to changes in environmental conditions, such as temperature, concentration, and $p$H. Using Monte Carlo simulation, we model bulk…

Soft Condensed Matter · Physics 2016-11-10 Matthew Urich , Alan R. Denton

Hydrogen has been the essential element in the development of atomic and molecular physics1). Moving to the properties of dense hydrogen has appeared a good deal more complex than originally thought by Wigner and Hungtinton in their seminal…

Materials Science · Physics 2019-06-14 Paul Loubeyre , Florent Occelli , Paul Dumas

Hydrogen intercalation in solids is common, complicated, and very difficult to monitor. In a new approach to the problem, we have studied the profile of hydrogen diffusion in single-crystal nanobeams and plates of VO2, exploiting the fact…

Strongly Correlated Electrons · Physics 2016-08-24 T. Serkan Kasırga , Jim M. Coy , Jae H. Park , David H. Cobden

Using path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD) simulation methods, we compute a coherent equation of state (EOS) of nitrogen that spans the liquid, warm dense matter (WDM), and plasma regimes.…

Plasma Physics · Physics 2016-03-23 K. P. Driver , B. Militzer