Quasi-Chemical Theory with Cluster Sampling from Ab Initio Molecular Dynamics: Fluoride (F) Anion Hydration
arXiv:1808.10737 · doi:10.1021/acs.jpca.8b08474
Abstract
Accurate predictions of the hydration free energy for anions typically have been more challenging than for cations. Hydrogen bond donation to the anion in hydrated clusters such as can lead to delicate structures. Consequently, the energy landscape contains many local minima, even for small clusters, and these minima present a challenge for computational optimization. Utilization of cluster experimental results for the free energies of gas-phase clusters shows that, even though anharmonic effects are interesting, they need not be troublesome magnitudes for careful applications of quasi-chemical theory to ion hydration. Energy-optimized cluster structures for anions can leave the central ion highly exposed and application of implicit solvation models to these structures can incur more serious errors than for metal cations. Utilizing cluster structures sampled from ab initio molecular dynamics simulations substantially fixes those issues.
arXiv comment6 pages, 5 figures
References in corpus (15)
- Hydrolysis of ferric ion in water and conformational equilibrium
- Tuning ion coordination preferences to enable selective permeation
- Free energy of liquid water on the basis of quasi-chemical theory and ab initio molecular dynamics
- Ab initio molecular dynamics calculations of ion hydration free energies
- Real single ion solvation free energies with quantum mechanical simulation
- Electrostatic solvation free energies of charged hard spheres using molecular dynamics with density functional theory interactions
- Balancing Local Order and Long-Ranged Interactions in the Molecular Theory of Liquid Water
- On "the complete basis set limit" and plane-wave methods in first-principles simulations of water
- Thermodynamics of water modeled using ab initio simulations
- Quasi-chemical theory with a soft cutoff
- Strontium and Barium in Aqueous Solution and a Potassium Channel Binding Site
- Regularizing binding energy distributions and thermodynamics of hydration. Application to water modeled with classical and ab initio simulations
- Water coordination structures and the excess free energy of the liquid
- Molecular packing and chemical association in liquid water simulated using ab initio hybrid Monte Carlo and different exchange-correlation functionals
- Solvophobic and solvophilic contributions in the water-to-aqueous guanidinium chloride transfer free energy of model peptides