Calculation of the Gibbs Free Energy of Solvation and Dissociation of HCl in Water via Monte Carlo Simulations and Continuum Solvation Models

Journal Article · Wed Aug 28 04:00:00 EDT 2013 · Physical Chemistry Chemical Physics. PCCP, 15(32):13578-13585

DOI:https://doi.org/10.1039/c3cp51762d· OSTI ID:1092646

McGrath, Matthew; Kuo, I-F W.; Ngouana, Brice F.; Ghogomu, Julius N.; Mundy, Christopher J.; Marenich, Aleksandr; Cramer, Christopher J.; Truhlar, Donald G.; Siepmann, Joern I.

The free energy of solvation and dissociation of hydrogen chloride in water is calculated through a combined molecular simulation quantum chemical approach at four temperatures between T = 300 and 450 K. The free energy is first decomposed into the sum of two components: the Gibbs free energy of transfer of molecular HCl from the vapor to the aqueous liquid phase and the standard-state free energy of acid dissociation of HCl in aqueous solution. The former quantity is calculated using Gibbs ensemble Monte Carlo simulations using either Kohn-Sham density functional theory or a molecular mechanics force field to determine the system’s potential energy. The latter free energy contribution is computed using a continuum solvation model utilizing either experimental reference data or micro-solvated clusters. The predicted combined solvation and dissociation free energies agree very well with available experimental data. CJM was supported by the US Department of Energy,Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1092646
• Report Number(s): PNNL-SA-95188; KC0301020
• Journal Information: Physical Chemistry Chemical Physics. PCCP, 15(32):13578-13585, Journal Name: Physical Chemistry Chemical Physics. PCCP, 15(32):13578-13585
• Country of Publication: United States
• Language: English