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arXiv · 1106.6216

Adsorption of finite polymers in different thermodynamic ensembles

Monika Möddel·Wolfhard Janke·Michael Bachmann
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Abstract

We investigate the cooperative effects of a single finite chain of monomers near an attractive substrate by first constructing a conformational pseudo-phase diagram based on the thermal fluctuations of energetic and structural quantities. Then, the adsorption transition is analyzed in more detail. This is conveniently done by a microcanonical analysis of densities of states obtained by extensive multicanonical Monte Carlo simulations. For short chains and strong surface attraction, the microcanonical entropy turns out to be a convex function of energy in the transition regime. This is a characteristic physical effect and deserves a careful consideration in analyses of cooperative macrostate transitions in finite systems.

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Monika Möddel, Wolfhard Janke, Michael Bachmann. 2011-06-30. Adsorption of finite polymers in different thermodynamic ensembles. https://doi.org/10.1016/j.cpc.2010.12.016

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