scholarly journals Gradient-driven diffusion using dual control volume grand canonical molecular dynamics

1998 ◽  
Author(s):  
A.M. Thompson ◽  
D.M. Ford ◽  
G.S. Heffelfinger
Keyword(s):  
Molecular Dynamics ◽  
Control Volume ◽  
Dual Control ◽  
Grand Canonical

Molecular Dynamics Computer Simulations of Diffusion in Porous Silicates

1994 ◽  
Vol 366 ◽  
Author(s):  
Grant S. Heffelfinger ◽  
Phillip I. Pohl ◽  
Laura J. D. Frink
Keyword(s):  
Experimental Data ◽  
Molecular Dynamics ◽  
Chemical Potential ◽  
Control Volume ◽  
Dual Control ◽  
Cylindrical Pore ◽  
Knudsen Effect ◽  
State Pressure ◽  
Molecular Sieving ◽  
Grand Canonical

ABSTRACTIn this work a newly developed dual control volume grand canonical molecular dynamics technique simulates the diffusion of gas in a cylindrical pore. This allows spatial variation of chemical potential and hence an accurate simulation of steady state pressure driven diffusion. The molecular sieving nature of imicroporous imogolite models and the Knudsen effect are discussed and compared with experimental data.

Gradient-Driven Diffusion Using Dual Control Volume Grand Canonical Molecular Dynamics (DCV-GCMD)

1995 ◽  
Vol 408 ◽  
Author(s):  
Frank Van Swol ◽  
Grant S. Heffelfinger
Keyword(s):  
Molecular Dynamics ◽  
Chemical Potential ◽  
Control Volume ◽  
Simulation Method ◽  
Steady State Mode ◽  
Transient Phenomena ◽  
Insertion And Deletion ◽  
Separate Control ◽  
Control Volumes ◽  
Grand Canonical

AbstractRecently we developed a new nonequilibrium molecular simulation method [1] that allows the direct study of interdiffusion in multicomponent mixtures. The method combines stochastic insertion and deletion moves characteristic of grand canonical (GC) simulations with molecular dynamics (MD) to control the chemical potential μi of a species i. Restricting the insertions and deletions to two separate control volumes (CV's) one can apply different μ's in distinct locations, and thus create chemical potential gradients. DCV-GCMD can be used to study transient phenomena such as the filling of micropores or used in steady-state mode to determine the diffusion coefficients in multicomponent fluid mixtures. We report on the effects of molecular interactions and demonstrate how in a sufficiently nonideal ternary mixture this can lead to up-hill or reverse diffusion. In addition we introduce a novel extension of DCV-GCMD that is specifically designed for the study of gradient-driven diffusion of molecules that are simply too large to be inserted and deleted.

Sign in / Sign up

Export Citation Format

Share Document