title: A partition function-based weighting scheme in force field parameter development using ab initio calculation results in global configurational space.
abstract: In force field parameter development using ab initio potential energy surfaces (PES) as target data, an important but often neglected matter is the lack of a weighting scheme with optimal discrimination power to fit the target data. Here, we developed a novel partition function-based weighting scheme, which not only fits the target potential energies exponentially like the general Boltzmann weighting method, but also reduces the effect of fitting errors leading to overfitting. The van der Waals (vdW) parameters of benzene and propane were reparameterized by using the new weighting scheme to fit the high-level ab initio PESs probed by a water molecule in global configurational space. The molecular simulation results indicate that the newly derived parameters are capable of reproducing experimental properties in a broader range of temperatures, which supports the partition function-based weighting scheme. Our simulation results also suggest that structural properties are more sensitive to vdW parameters than partial atomic charge parameters in these systems although the electrostatic interactions are still important in energetic properties. As no prerequisite conditions are required, the partition function-based weighting method may be applied in developing any types of force field parameters.
authors: Graduate Program in Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.
authors: Yao
authors: Y
authors: Wu
authors: Xiaodong
authors: X
authors: Dai
authors: Niu
authors: N
authors: Huang
authors: Lifeng
authors: L
authors: Zhao
mesh_terms: D001554:Benzene / Q000737:chemistry*; D011407:Propane / Q000737:chemistry*; D011789:Quantum Theory; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D001554:Benzene; D011407:Propane