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arXiv · 0902.3112

A one-dimensional dipole lattice model for water in narrow nanopores

Jürgen Köfinger·Gerhard Hummer·Christoph Dellago
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Abstract

We present a recently developed one-dimensional dipole lattice model that accurately captures the key properties of water in narrow nanopores. For this model, we derive three equivalent representations of the Hamiltonian that together yield a transparent physical picture of the energetics of the water chain and permit efficient computer simulations. In the charge representation, the Hamiltonian consists of nearest-neighbor interactions and Coulomb-like interactions of effective charges at the ends of dipole ordered segments. Approximations based on the charge picture shed light on the influence of the Coulomb-like interactions on the structure of nanopore water. We use Monte Carlo simulations to study the system behavior of the full Hamiltonian and its approximations as a function of chemical potential and system size and investigate the bimodal character of the density distribution occurring at small system sizes.

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Jürgen Köfinger, Gerhard Hummer, Christoph Dellago. 2009-02-18. A one-dimensional dipole lattice model for water in narrow nanopores. https://doi.org/10.1063/1.3106223

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