English
Related papers

Related papers: Molecular Hydrogen Formation on Low Temperature Su…

200 papers

We report on the detection of deuterated molecular hydrogen, HD, at $z = 0.18$. HD and H$_{\rm 2}$ are detected in HST/COS data of a low metallicity ($Z \sim 0.07Z_\odot$) damped Ly$\alpha$ system at $z = 0.18562$ toward QSO B0120$-$28,…

Astrophysics of Galaxies · Physics 2015-06-18 Cristina M. Oliveira , Kenneth R. Sembach , Jason Tumlinson , John O'Meara , Christopher Thom

Context: The HD and H2 molecules play important roles in the cooling of primordial and very metal-poor gas at high redshift. Aims: Grain surface and gas phase formation of HD and H2 is investigated to assess the importance of trace amounts…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 S. Cazaux , M. Spaans

We derive total (atomic + molecular) hydrogen densities in giant molecular clouds (GMCs) in the nearby spiral galaxy M33 using a method that views the atomic hydrogen near regions of recent star formation as the product of…

Astrophysics of Galaxies · Physics 2015-05-27 J. S. Heiner , R. J. Allen , P. C. van der Kruit

Methanol is formed via surface reactions on icy dust grains. Methanol is also detected in the gas-phase at temperatures below its thermal desorption temperature and at levels higher than can be explained by pure gas-phase chemistry. The…

Solar and Stellar Astrophysics · Physics 2018-05-02 N. F. W. Ligterink , C. Walsh , R. G. Bhuin , S. Vissapragada , J. Terwisscha van Scheltinga , H. Linnartz

Context. The photolysis of hydrogenated amorphous carbon, a-C(:H), dust by UV photon-irradiation in the laboratory leads to the release of H2 as well as other molecules and radicals. This same process is also likely to be important in the…

Astrophysics of Galaxies · Physics 2015-09-23 A. P. Jones , E. Habart

The molecular dynamics (MD) approach is an effective tool for investigating atomistic dynamical phenomena at the surface of materials under strong laser irradiation. Therefore, numerous laser ablation MD simulation studies have been…

Materials Science · Physics 2023-02-14 Ryo Kobayashi , Tomohito Otobe

Monolayer transition metal dichalcogenides (TMDs) show an optimal surface-to-volume ratio and are thus promising candidates for novel molecule sensor devices. It was recently predicted that a certain class of molecules exhibiting a large…

We developed a highly hydrogen-sensitive thermal desorption spectroscopy (HHS-TDS) system to detect and quantitatively analyze low hydrogen concentrations in thin films. The system was connected to an in situ sample-transfer chamber system,…

Materials Science · Physics 2017-05-08 Taku Hanna , Hidenori Hiramatsu , Isao Sakaguchi , Hideo Hosono

We present a path-integral Monte Carlo study of dissociation in dense hydrogen ($1.75 \leq r_s \leq 2.2$, with $r_s$ the Wigner sphere radius). As temperature is lowered from $10^5$ to 5000 K, a molecular hydrogen gas forms spontaneously…

Condensed Matter · Physics 2009-10-28 W. R. Magro , D. M. Ceperley , C. Pierleoni , B. Bernu

We use UV measurements of interstellar CO towards nearby stars to calculate the density in the diffuse molecular clouds containing the molecules responsible for the observed absorption. Chemical models and recent calculations of the…

Astrophysics of Galaxies · Physics 2015-06-16 Paul F. Goldsmith

Understanding the phase transition mechanisms in two-dimensional (2D) materials is a key to precisely tailor their properties at the nanoscale. Molybdenum ditelluride (MoTe2) exhibits multiple phases at room temperature, making it a…

Relaxed atomic geometries and chemisorption energies have been calculated for the dissociative adsorption of molecular hydrogen on vicinal Si(001) surfaces. We employ density-functional theory, together with a pseudopotential for Si, and…

Condensed Matter · Physics 2009-10-31 E. Pehlke , P. Kratzer

We demonstrate the measurement and manipulation of the temperature of cold CO molecules in a microchip environment. Through the use of time-resolved spatial imaging, we are able to observe the phase-space distribution of the molecules, and…

We study the rotational and vibrational heating of diatomic molecules placed near a surface at finite temperature on the basis of macroscopic quantum electrodynamics. The internal molecular evolution is governed by transition rates that…

Quantum Physics · Physics 2009-12-14 Stefan Yoshi Buhmann , M. R. Tarbutt , Stefan Scheel , E. A. Hinds

A roughly constant temperature over a wide range of densities is maintained in molecular clouds through radiative heating and cooling. An isothermal equation of state is therefore frequently employed in molecular cloud simulations. However,…

Astrophysics · Physics 2009-11-11 G. Pavlovski , M. D. Smith , M. -M. Mac Low

The mechanisms of magnesium hydride formation and thermal decomposition are directly examined using in-situ imaging.

Materials Science · Physics 2010-02-25 T. Herranz , K. F. McCarty , B. Santos , M. Monti , J. de la Figuera

Transition metal dichalcogenides (TMDs) are a class of two-dimensional (2D) materials been widely studied for emerging electronic properties. In this work, we use computational simulations to examine the water adsorption on TMDs…

Computational Physics · Physics 2024-02-20 Siheng Li , Keyang Liu , Jiří Klimeš , Ji Chen

The present study experimentally demonstrated that solid H2O is formed through the surface reaction OH + H2 at 10 K. This is the first experimental evidence of solid H2O formation using hydrogen in its molecular form at temperatures as low…

Astrophysics of Galaxies · Physics 2012-03-29 Y. Oba , N. Watanabe , T. Hama , K. Kuwahata , H. Hidaka , A. Kouchi

We investigate the adsorption of molecular hydrogen on pristine zinc oxide (ZnO) platelets. The volumetric and gravimetric hydrogen storage capacities of the ZnO monolayers are evaluated in a broad range of thermodynamic conditions (i.e.,…

Palladium (Pd) catalysts have been extensively studied for the direct synthesis of H2O through the hydrogen oxidation reaction at ambient conditions. This heterogeneous catalytic reaction not only holds considerable practical significance…

Materials Science · Physics 2024-04-23 Yukun Liu , Kunmo Koo , Zugang Mao , Xianbiao Fu , Xiaobing Hu , Vinayak P. Dravid