Translational and rotational diffusion of model nanocolloidal dispersions studied by molecular dynamics simulations

Heyes, D. M.; Nuevo, María J.; Morales, Juan J.; Brańka, A. C.

doi:10.1088/0953-8984/10/45/005

Cited by 41 publications

(39 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, as previously done for thermodynamic properties, for the same thermodynamic states given in Table II, between mass diffusion and viscosity is function only of temperature and of particle size 24 and seems to make sense even for non colloidal systems 38,39 .…”

Section: Direct Transport Propertiessupporting

confidence: 66%

Molecular dynamics study of the repulsive form influence of the interaction potential on structural, thermodynamic, interfacial, and transport properties

Galliéro¹,

Boned²

2008

The Journal of Chemical Physics

View full text Add to dashboard Cite

In this work, using extensive molecular dynamics simulations of several thermophysical properties, it is proposed to analyze possible relationships (in the corresponding states sense) between monoatomic fluids for which the repulsive interactions are modeled by an inverse n-power form, the Lennard-Jones 12-6 (LJ), or by an exponential one, the exponential-6 (Exp-6). To compare results between them, two possible definitions of Exp-6 potentials "equivalent" to the LJ one are proposed. In pure fluids, for a large range of thermodynamic conditions, the properties computed are the surface tension, liquid/vapour equilibrium densities, one-phase potential energy, pressure, isometric heat capacity, thermal pressure coefficient and self-diffusion, shear viscosity, thermal conductivity. Additionally, thermodiffusion (Soret effect) has been considered in "isotopic" equimolar mixtures. It is shown that, despites similarities exhibited by alike radial distribution functions, differences exist between the thermodynamic properties values provided by the LJ fluid and the two "equivalent" Exp-6 fluids. Nevertheless, quite surprisingly, when temperature and density are used as inputs, all three direct transport properties are shown to be nearly independent of the 2 choice of the potential tested. Unexpectedly, these similarities hold even for thermodiffusion which is a priori very sensitive to the nature of the interactions. These results indicate that the use of an Exp-6 potential form to describe non bonded/non polar interaction in molecular simulation is an alternative (more physically acceptable) to the LJ potential when dealing simultaneously with thermodynamic and transport properties. However, when only transport properties are considered (including thermodiffusion), the Exp-6 potential form should not lead to any differences compared to the LJ one.3

show abstract

Section: Direct Transport Propertiessupporting

confidence: 66%

Molecular dynamics study of the repulsive form influence of the interaction potential on structural, thermodynamic, interfacial, and transport properties

Galliéro¹,

Boned²

2008

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…It has long been recognized that the dynamic and transport properties of nanoparticles, in the bulk [4][5][6][7][8] and at interfaces, may be significantly different to those of larger particles. The translational motion of particles at interfaces is important in understanding the interfacial self-assembly processes and in the use of nanoparticles as tracer particles in micro-and nanorheology [9,10].…”

Section: Introductionmentioning

confidence: 99%

Molecular simulation of nanoparticle diffusion at fluid interfaces

Cheung

2010

Chemical Physics Letters

View full text Add to dashboard Cite

Using molecular dynamics simulations the transport properties of a model nanoparticle in solution are studied. In bulk solvent the translational diffusion coefficients are in good agreement with previous simulation and experimental work, while the rotational diffusion is more rapid than in previous simulations. When the nanoparticle is adsorbed at a liquid-liquid interface it becomes strongly attached to the interface. This leads to highly anisotropic motion with in-plane diffusion being several orders of magnitude larger than out-of-plane diffusion. By contrast the rotational diffusion is only slightly changed when the particle is adsorbed at the interface.

show abstract

“…At present we lack any quantitative validation of these MD/ Langevin domains. In order to obtain a clearer understanding of the transition between the behaviour of simple fluids and those of colloidal liquids we have carried out a series of molecular dynamics simulations of a single model nanocolloidal particle in a 'sea' of liquid solvent molecules [10][11][12][13]. The dynamics of both the nanocolloidal particle and solvent molecules are generDownloaded by [University of Leeds] at 06:45 21 November 2014 ated by a numerical integration of Newton's equations of motion.…”

Section: Introductionmentioning

confidence: 99%

Calculation of nanocolloidal liquid time scales by molecular dynamics simulations

Heyes

Brańka

1999

Molecular Physics

View full text Add to dashboard Cite

Molecular dynamics, MD, simulations have been used to calculate the translational and rotational relaxation dynamics of model atomistically rough spherical nanocolloidal particles in solution at infinite dilution by immersing a single Lennard-Jones cluster in a molecularly discrete solvent. Key time scales characterizing colloidal particle dynamical relaxation were computed from time correlation functions. For translational motion these were r,, the colloidal velocity relaxation time, Tfr the hydrodynamic relaxation time and the time scale for significant particle displacement, rd. We show that T, N Tf when the relative mass density of the colloidal particle divided by the bulk density of the solvent is ca. p* = 20, in agreement with theoretical predictions. Preliminary evidence from the velocity autocorrelation functions, VACF, of the nanocolloidal particle also supports the theoretical treatments that the transition from the Liouville to Fokker-Planck description (evident by exponential decay in the VACF) is determined by both the colloidal particle mass and size. We calculated the relaxation times for angular velocity relaxation, T~ and reorientation, ru and found them to scale reasonably well with the relaxation time for the free rotor, for size dependence but not so well for mass dependence. The angular velocity correlation function of 13 atom clusters departed from Langevin (exponential) relaxation also for p* < 20. The rotational self-diffusion coefficient was also non-classical in this range.

show abstract

Translational and rotational diffusion of model nanocolloidal dispersions studied by molecular dynamics simulations

Cited by 41 publications

References 19 publications

Molecular dynamics study of the repulsive form influence of the interaction potential on structural, thermodynamic, interfacial, and transport properties

Molecular dynamics study of the repulsive form influence of the interaction potential on structural, thermodynamic, interfacial, and transport properties

Molecular simulation of nanoparticle diffusion at fluid interfaces

Calculation of nanocolloidal liquid time scales by molecular dynamics simulations

Contact Info

Product

Resources

About