Temperature and density dependence of the self-diffusion coefficient and Mori coefficients of Lennard-Jones fluids by molecular dynamics simulation

1997 ◽  
Vol 55 (4) ◽  
pp. 4217-4224 ◽  
Author(s):  
María J. Nuevo ◽  
Juan J. Morales ◽  
David M. Heyes
2009 ◽  
Vol 289-292 ◽  
pp. 609-614 ◽  
Author(s):  
Andreas Meyer ◽  
Jürgen Horbach ◽  
O. Heinen ◽  
Dirk Holland-Moritz ◽  
T. Unruh

Self diffusion in liquid titanium was measured at 2000K by quasielastic neutron scattering (QNS) in combination with container less processing via electromagnetic levitation. At small wavenumbers q the quasielastic signal is dominated by incoherent scattering. Up to about 1.2 °A−1 the width of the quasielastic line exhibits a q2 dependence as expected for long range atomic transport, thus allowing to measure the self diffusion coefficient DTi. As a result the value DTi = (5.3± 0.2)× 10−9 m2s−1 was obtained.With a molecular dynamics (MD) computer simulation using an embedded atom model (EAM) for Ti, the self diffusion coefficient is determined from the mean square displacement as well as from the decay of the incoherent intermediate scattering function at different q. By comparing both methods, we show that the hydrodynamic prediction of a q2 dependence indeed extends up to about 1.2 °A−1. Since this result does not depend significantly on the details of the interatomic potential, our findings show that accurate values of self diffusion coefficients in liquid metals can be measured by QNS on an absolute scale.


2020 ◽  
Vol 27 (1) ◽  
pp. 13-22
Author(s):  
Md Khorshed Alam ◽  
Wataru Yamamoto ◽  
Hiromitsu Takaba

In this work, molecular dynamics (MD) study of triglyme (G3) solution containing lithium bis (trifluoro methyl sulfonyl) amide (Li[TFSA]) were investigated using classical atomistic force fields. G3 is a typical solvent used in non-aqueous Li-air battery. It shows here coordination of Li+ with G3 and [TFSA]- does not significantly change with increasing the concentration of G3 but self-diffusion coefficient of all the ions increases with increasing G3 concentration. The density of [Li(G3)[TFSA] complex decreases with increasing G3 concentration which lead to accelerate diffusivity of ions. Bangladesh Journal of Physics, 27(1), 13-22, June 2020


2001 ◽  
Vol 56 (3-4) ◽  
pp. 273-278 ◽  
Author(s):  
Masahiko Matsumiya ◽  
Ryuzo Takagi

Abstract Molecular dynamics simulations have been performed on molten (Dy1/3,K)Cl at 1093 K in order to compare the calculated self-exchange velocity (SEV), self-diffusion coefficient (D) and electrical con­ductivity with the corresponding experimental results. It was found that SEV, v, and D of potassium de­ crease with increasing concentration of dysprosium, as expected from the internal mobility, b. The decrease of bK, vK, and DK are ascribed to the tranquilization effect by Dy3+ which strongly inter­ acts with CP. On the contrary, bDy, vDy, and DDy increase with increasing concentration of Dy3+. This may be attributed to the stronger association of Dy3+ with Cl- due to the enhanced charge asym­ metry of the two cations neighboring to the Cl-. In addition, the sequence of the calculated SEV's, D's and electrical conductivities for the various compositions were consistent with those of the referred ex­ perimental results.


2018 ◽  
Vol 16 (2) ◽  
Author(s):  
Niraj Kumar ◽  
Narayan Prasad Adhikari

Molecular Dynamics simulation was performed using 2 xenon atoms as solute and 300 water molecules as solvent. We have studied the structural properties as well as transport property. As structural properties, we have determined the radial distribution function (RDF) of xenon-xenon, xenon-water, and water-water interactions. Study of RDF of xenon-xenon and oxygen-oxygen interactions of water shows that there is hydrophobic behavior of xenon in the presence of water. We have studied the self diffusion coefficient of xenon, water, and mutual diffusion coefficients of xenon in water. The self diffusion coefficient of xenon was estimated using both mean-squared displacement (MSD) and velocity autocorrelation function (VACF), while only MSD was used for water. The temperature dependence of the diffusion coefficient of xenon and water were found to follow the Arrhenius behavior. The activation energies obtained are 12.156 KJ/mole with MSD and 14.617 KJ/mole with VACF in the temperature range taken in this study.


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