Force Field for Monovalent, Divalent, and Trivalent Cations Developed under the Solvent Boundary Potential

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• 作者：Youngdo Won
• 刊名：The Journal of Physical Chemistry A
• 出版年：2012
• 出版时间：November 29, 2012
• 年：2012
• 卷：116
• 期：47
• 页码：11763-11767
• 全文大小：235K
• 年卷期：v.116,no.47(November 29, 2012)
• ISSN：1520-5215

文摘

Presented are parameters for mono-, di-, and trivalent cations compatible with the CHARMM additive force field and the TIP3P water model. Thermodynamic perturbation molecular dynamics simulations were performed for the cations located at the center of a TIP3P water sphere under a solvent boundary potential. A series of perturbations generated free energies of hydration indexed by the two Lennard-Jones parameters, 蔚 and R_min. Interpolating the experimental free energies of hydration showed that multiple combinations of 蔚 and R_min values reproduced the free energies of hydration for each ion. To overcome this nonunique parameter problem, the hydration shell model in combination with an empirical scaling parameter was applied to assign values for each ion. R_min values were then identified via interpolation of the calculated free energies of hydration. The presented parameters are anticipated to be of utility for simulations of ions, including ions complexed to proteins.