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arXiv · 1107.0305

Statistical Mechanics of Aggregation and Crystallization for Semiflexible Polymers

Christoph Junghans·Michael Bachmann·Wolfhard Janke
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Abstract

By means of multicanonical computer simulations, we investigate thermodynamic properties of the aggregation of interacting semiflexible polymers. We analyze a mesoscopic bead-stick model, where nonbonded monomers interact via Lennard-Jones forces. Aggregation turns out to be a process, in which the constituents experience strong structural fluctuations, similar to peptides in coupled folding-binding cluster formation processes. In contrast to a recently studied related proteinlike hydrophobic-polar heteropolymer model, aggregation and crystallization are separate processes for a homopolymer with the same small bending rigidity. Rather stiff semiflexible polymers form a liquid-crystal-like phase, as expected. In analogy to the heteropolymer study, we find that the first-order-like aggregation transition of the complexes is accompanied by strong system-size dependent hierarchical surface effects. In consequence, the polymer aggregation is a phase-separation process with entropy reduction.

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Christoph Junghans, Michael Bachmann, Wolfhard Janke. 2011-07-01. Statistical Mechanics of Aggregation and Crystallization for Semiflexible Polymers. https://doi.org/10.1209/0295-5075/87/40002

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