Development of a 鈥淔irst Principles鈥?Water Potential with Flexible Monomers. II: Trimer Potential Energy Surface, Third Virial Coefficient, and Small Clusters

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• 作者：Volodymyr Babin ; Gregory R. Medders ; Francesco Paesani
• 刊名：Journal of Chemical Theory and Computation
• 出版年：2014
• 出版时间：April 8, 2014
• 年：2014
• 卷：10
• 期：4
• 页码：1599-1607
• 全文大小：433K
• 年卷期：v.10,no.4(April 8, 2014)
• ISSN：1549-9626

文摘

A full-dimensional potential energy function (MB-pol) for simulations of water from the dimer to bulk phases is developed entirely from 鈥渇irst principles鈥?by building upon the many-body expansion of the interaction energy. Specifically, the MB-pol potential is constructed by combining a highly accurate dimer potential energy surface [J. Chem. Theory Comput. 2013, 9, 5395] with explicit three-body and many-body polarization terms. The three-body contribution, expressed as a combination of permutationally invariant polynomials and classical polarizability, is derived from a fit to more than 12000 three-body energies calculated at the CCSD(T)/aug-cc-pVTZ level of theory, imposing the correct asymptotic behavior as predicted from 鈥渇irst principles鈥? Here, the accuracy of MB-pol is demonstrated through comparison of the calculated third virial coefficient with the corresponding experimental data as well as through analysis of the relative energy differences of small clusters.