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arXiv · 1603.08787

$\mathcal {C}-$IBI: Targeting cumulative coordination within an iterative protocol to derive coarse-grained models of (multi-component) complex fluids

Tiago E. de Oliveira·Paulo A. Netz·Kurt Kremer·Christoph Junghans·Debashish Mukherji
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Abstract

We present a coarse-graining strategy that we test for aqueous mixtures. The method uses pair-wise cumulative coordination as a target function within an iterative Boltzmann inversion (IBI) like protocol. We name this method coordination iterative Boltzmann inversion ($\mathcal {C}-$IBI). While the underlying coarse-grained model is still structure based and, thus, preserves pair-wise solution structure, our method also reproduces solvation thermodynamics of binary and/or ternary mixtures. Additionally, we observe much faster convergence within $\mathcal {C}-$IBI compared to IBI. To validate the robustness, we apply $\mathcal {C}-$IBI to study test cases of solvation thermodynamics of aqueous urea and a triglycine solvation in aqueous urea.

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Tiago E. de Oliveira, Paulo A. Netz, Kurt Kremer, Christoph Junghans, Debashish Mukherji. 2016-03-29. $\mathcal {C}-$IBI: Targeting cumulative coordination within an iterative protocol to derive coarse-grained models of (multi-component) complex fluids. https://doi.org/10.1063/1.4947253

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