Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-8-13
pubmed:abstractText
We present results from molecular dynamics simulations for the anisotropic self-diffusion tensor and the velocity autocorrelation functions of monodisperse systems of dense linear chain molecules under flow. Two molecular models are used in these simulations: The finitely extensible nonlinear elastic chain and the freely jointed tangent sphere chain. Nonequilibrium molecular dynamics is used to simulate these systems under planar Couette flow and planar extensional flow. Under planar extensional flow, results presented here are the first, from simulation, for diffusion and velocity autocorrelation functions of molecules, while for planar Couette flow, we compare the broadest range of conditions. An explicit derivation is provided of the Green-Kubo expression for the diffusion tensor. This expression is then used to derive the relation involving the mean-squared displacement-an often used alternative method to calculate diffusion coefficients. Velocity autocorrelation functions have been used, in combination with results on the alignment of molecules from a previous paper, to provide some details of the molecular scale dynamics that influence diffusive transport under flow.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Aug
pubmed:issn
1089-7690
pubmed:author
pubmed:issnType
Electronic
pubmed:day
7
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
054904
pubmed:year
2009
pubmed:articleTitle
Diffusion of linear polymer melts in shear and extensional flows.
pubmed:affiliation
Centre for Molecular Simulation, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. tomahunt@gmail.com
pubmed:publicationType
Journal Article