From Implicit to\nExplicit: An Interaction-Reorganization\nApproach to Molecular Solvation Energy

Accurate calculation of solvation energies has long fascinated\nresearchers, but complex interactions within bulk water molecules\npose significant challenges. Currently, molecular solvation energy\ncalculations are mostly based on implicit solvent approximations in\nwhich the solvent molecules are treated as continuum dielectric media.\nHowever, the implicit solvent approach is not ideal because it lacks\ncertain real solvation effects, such as that of the first solvation\nshell, etc. Here, we propose an explicit solvent approach, interaction-reorganization\nsolvation (IRS) method, for molecular solvation energy calculations.\nThe IRS approach achieves predictive accuracy comparable to that of\nthe widely recognized solvation model based on the density (SMD) method\nand is significantly more accurate than that of the Poisson–Boltzmann/generalized\nBorn surface area (PB/GBSA) methods. This is demonstrated in both\nthe correlation coefficient and the mean absolute error (MAE) with\nrespect to the experimental data. The IRS method is based on molecular\ndynamics simulation in explicit solvent and does not need to solve\nPoisson–Boltzmann or Schrödinger equations. On the other\nhand, the accuracy of the IRS method does depend on the accuracy of\nthe molecular force field used in MD simulations. We expect that the\nIRS method will be very useful for the solvation energy calculations\nof molecules.