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arXiv · 0802.4402

Generating multi-chain configurations of an inhomogeneous melt from the knowledge of single-chain properties

Martin Hömberg·Marcus Müller
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Abstract

Mean-field techniques provide a rather accurate description of single-chain conformations in spatially inhomogeneous polymer systems containing interfaces or surfaces. Intermolecular correlations, however, are not described by the mean-field approach and information about the distribution of distance between different molecules is lost. Based on the knowledge of the exact equilibrium single-chain properties in contact with solid substrates, we generate multi-chain configurations that serve as nearly equilibrated starting configurations for molecular dynamics simulations by utilizing the packing algorithm of Auhl and co-workers [J. Chem. Phys. 119, 12718 (2003)] for spatially inhomogeneous systems, i.e., a thin polymer film confined between two solid substrates. The single-chain conformations are packed into the thin film conserving the single-chain properties and simultaneously minimizing local fluctuations of the density. The extent to which enforcing the near-incompressibility of a dense polymer liquid during the packing process is able to re-establish intermolecular correlations is investigated by monitoring intermolecular correlation functions and the structure function of density fluctuations as a function of the distance from the confining solid substrates.

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Martin Hömberg, Marcus Müller. 2008-02-29. Generating multi-chain configurations of an inhomogeneous melt from the knowledge of single-chain properties. https://doi.org/10.1063/1.2939009

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