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arXiv · 1506.05437

On the representation of many-body interactions in water

Gregory R. Medders·Andreas W. Gotz·Miguel A. Morales·Francesco Paesani
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Abstract

Recent work has shown that the many-body expansion of the interaction energy can effectively be used to develop analytical representations of global potential energy surfaces (PESs) for water. In this study, the role of short- and long-range contri- butions at different orders is investigated by analyzing water potentials that treat the leading terms of the many-body expansion through implicit (i.e., TTM3-F and TTM4-F PESs) and explicit (i.e., WHBB and MB-pol PESs) representations. It is found that explicit short-range representations of 2-body and 3-body interactions along with a physically correct integration of short- and long-range contributions are necessary for an accurate representation of the water interactions from the gas to the condensed phase. Similarly, a complete many-body representation of the dipole moment surface is found to be crucial to reproducing the correct intensities of the infrared spectrum of liquid water.

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Gregory R. Medders, Andreas W. Gotz, Miguel A. Morales, Francesco Paesani. 2015-06-17. On the representation of many-body interactions in water. https://doi.org/10.1063/1.4930194

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