Molecular dynamics study of solid argon with N2, O2, and CO impurities

Molecular dynamics calculations employing atom–atom (exp-6) potentials are reported for solid argon in which 5% of the lattice sites are occupied by diatomic molecules. At temperatures close to the melting point (T ~ 80 K) the molecules are reorienting rapidly with no preferred orientation. Upon cooling, however, a distinct preference is observed for the crystallographic [Formula: see text] direction. Power spectra that characterize the translational and reorientational motions in the system have been evaluated. The results are discussed in light of available experimental data.

Download Full-text

A Theoretical Study Of The Energetics And Vibrational Spectra Of Oxygenated (100) Diamond Surfaces

MRS Proceedings ◽

10.1557/proc-416-281 ◽

1995 ◽

Vol 416 ◽

Author(s):

S. Skokov ◽

B. Weiner ◽

M. Frenklach

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Hydrogen Bonds ◽

Vibrational Spectra ◽

Theoretical Study ◽

Local Environment ◽

Hydroxyl Groups ◽

Vibrational Modes ◽

Diamond Surfaces ◽

Molecular Dynamics Calculations

ABSTRACTStatic quantum ab initio and quantum semiempirical molecular dynamics calculations were employed to study reconstructions of (100) diamond surfaces in presence of hydrogen and oxygen. The results indicate that the energetically most favorable structures of oxygenated surfaces are those with chemisorbed hydroxyl groups. It was found that hydrogen bonds are formed among chemisorbed oxygenated species. The formation of these hydrogen bonds is shown to be an important factor in stabilization of adlayers. A number of important vibrational modes characteristic of oxygenated diamond surfaces were identified. The analysis of surface vibrational spectra demonstrates the influence of the local environment on the position of vibrational modes and can be useful for interpretation of experimental data.

Download Full-text

A molecular dynamics study of ices III and V using TIP4P and TIP5P water models

Canadian Journal of Physics ◽

10.1139/p02-136 ◽

2003 ◽

Vol 81 (1-2) ◽

pp. 11-16 ◽

Cited By ~ 16

Author(s):

R B Ayala ◽

V Tchijov

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Molecular Interactions ◽

Specific Volume ◽

Molecular Dynamics Calculations ◽

Water Models ◽

Good Agreement

Simulations of ices III and V are performed using molecular dynamics calculations in the NPT ensemble. To represent molecular interactions in both ices, two potentials, TIP4P and TIP5P, are used. The specific volume of ice III is calculated as a function of temperature at pressure P = 250 MPa, as well as a function of pressure at temperature T = 246 K. For ice V, the specific volume is calculated as a function of temperature at P = 500 MPa and as a function of pressure at T = 238 K. In both cases, both TIP4P and TIP5P models are used. The results of the calculations are in good agreement with the experimental data of other researchers. PACS No.: 31.15Qg

Download Full-text

Molecular Dynamics Calculations of InSb Thermal Conductivity

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.297-301.1400 ◽

2010 ◽

Vol 297-301 ◽

pp. 1400-1407

Author(s):

Giovano de Oliveira Cardozo ◽

José Pedro Rino

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

Molecular Dynamics ◽

Infinite System ◽

Thermal Conductivity Coefficient ◽

Direct Method ◽

Molecular Dynamics Calculations ◽

Non Equilibrium Molecular Dynamics ◽

Three Body ◽

Non Equilibrium

Equilibrium and non-equilibrium molecular dynamics calculations of thermal conductivity coefficient are presented for bulk systems of InSb, using an effective two- and three-body inter atomic potential which demonstrated to be very transferable. In the calculations, the obtained coefficients were comparable to the experimental data. In the case of equilibrium simulations a Green-Kubo approach was used and the thermal conductivity was calculated for five temperatures between 300 K and 900 K. For the non equilibrium, or direct method, which is based on the Fourier’s law, the thermal conductivity coefficient was determined at a mean temperature of 300K. In this case it was used a pair of reservoirs, placed at a distance L from each other, and with internal temperatures fixed in 250 K, for the cold reservoir, and 350 K for the hot one. In order to obtain an approach to an infinite system coefficient, four different values of L were used, and the data was extrapolated to L→∞.

Download Full-text

Infrared absorption in doped rare gas crystals

Canadian Journal of Physics ◽

10.1139/p83-200 ◽

1983 ◽

Vol 61 (11) ◽

pp. 1545-1548 ◽

Cited By ~ 6

Author(s):

J. Vermesse ◽

Dominique Levesque ◽

Jean-Jacques Weis ◽

Michael L. Klein

Keyword(s):

Experimental Data ◽

Gas Phase ◽

Infrared Absorption ◽

Rare Gas ◽

Pair Potentials ◽

Molecular Dynamics Calculations ◽

Phase Data ◽

Interaction Dipole Moment ◽

Three Body ◽

Solid Argon

Molecular dynamics calculations based upon realistic pair potentials plus three body forces are used to investigate the properties of solid argon doped wth 2% krypton. The infrared absorption, which is computed using an expression for the interaction dipole moment derived from gas phase data, agrees well with experimental data.

Download Full-text

Effects of Chlorine on Aluminum Refining: A Review and an Ab Initio Molecular Dynamics Study

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.467-469.1404 ◽

2011 ◽

Vol 467-469 ◽

pp. 1404-1409 ◽

Cited By ~ 1

Author(s):

Yan Liu ◽

Bao De Sun ◽

Jun Wang ◽

Yong Bing Dai

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Ab Initio ◽

Hydrogen Diffusion ◽

Liquid Aluminum ◽

Refining Process ◽

Ab Initio Molecular Dynamics ◽

Molecular Dynamics Calculations ◽

Comprehensive Introduction ◽

Diffusion Of Hydrogen

A comprehensive introduction of current aluminum refining technology is reviewed in this work especially the effects of chlorine on refining process is discussed. The mechanism of chlorine on improving hydrogen diffusion has been studied by ab initio molecular dynamics calculations and we obtain the diffusivity of hydrogen in liquid aluminum which is in agreement with the experimental data. It can be concluded that the diffusion of hydrogen in aluminum melts can be enhanced on the presence of chlorine.

Download Full-text

Solvation ofN-Methylformamide by Ethanol: A Comparison of Molecular Dynamics Calculations with the Experimental Data

The Journal of Physical Chemistry B ◽

10.1021/jp012833x ◽

2002 ◽

Vol 106 (4) ◽

pp. 861-869 ◽

Cited By ~ 5

Author(s):

Jan Zielkiewicz ◽

Jan Mazerski

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Molecular Dynamics Calculations

Download Full-text

Thermal Conductivity of Solid Argon Nano-Films from Molecular Dynamics Simulations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.221.598 ◽

2011 ◽

Vol 221 ◽

pp. 598-603 ◽

Cited By ~ 1

Author(s):

Lian Xiang Ma ◽

Yuan Zheng Tang ◽

Yan He

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

Molecular Dynamics ◽

Film Thickness ◽

Computer Program ◽

Molecular Dynamics Simulations ◽

Film Plane ◽

Nonequilibrium Molecular Dynamics ◽

Dynamics Simulations ◽

Solid Argon

Thermal conductivity of L-J potential solid argon nano-films is calculated by equilibrium molecular dynamics (EMD) and nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 30K to 80K. A LAMMPS computer program has been modified based on classical molecular dynamics. It can be directly used to calculate the thermal conductivity of nano-films in the direction perpendicular to the film plane. Thermal conductivity calculated from this program is compared with experimental data. It is found that this computer program is competent to calculate the thermal conductivity of solid nano-films. It is also found that thermal conductivity is dependent on the simulation temperature and film thickness.

Download Full-text