A Mechanism for Ion Transport Across the Water/Dichloromethane Interface: A Molecular Dynamics Study Using Polarizable Potential Models
- BATTELLE (PACIFIC NW LAB)
In this work, we used molecular dynamics techniques and mean force approaches to compute the ion transfer free energy for the water/dichloromethane liquid-liquid interface. We used polarizable potential models to describe the interactions among the species, and both forward and reverse directions were carried out to estimate the error bar of the computed free energy results. Based on the results of our calculations, we have proposed a mechanism that describes the transport of a chlorine ion across the interface. The computed ion transfer free energy is 14 & No.177; 2 kcal/mol, which is in reasonable agreement with the experimentally reported value of 10 kcal/mol. A smooth transition from the aqueous phase to the non-aqueous phase on the free energy profile clearly indicates that the ion transfer mechanism is a nonactivated process. The computed hydration number for the chlorine ion indicates that some water molecules are associated with the ion inside the non-aqueous phase. This result is in excellent agreement with the experimental interpretation of the ion transfer mechanism reported recently by Osakai et al. (J. Phys. Chem. 1997, 101, 8341).
- Research Organization:
- Pacific Northwest National Lab., Richland, WA (US)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 15005641
- Report Number(s):
- PNNL-SA-33583; KC0301020; TRN: US0305579
- Journal Information:
- Journal of Physical Chemistry B, Vol. 105, Issue 4; Other Information: PBD: 1 Feb 2001
- Country of Publication:
- United States
- Language:
- English
Similar Records
Molecular dynamics study of benzene-benzene and benzene-potassium ion interactions using polarizable potential models
Molecular Mechanism of Transporting a Polarizable Iodide Anion Across the Water-CCl4 Liquid/Liquid Interface