Investigation of Interfacial and Bulk Dissociation of HBr, HCl, and HNO3 Using Density Functional Theory-Based Molecular Dynamics Simulations

December 18, 2014

Journal Article

Investigation of Interfacial and Bulk Dissociation of HBr, HCl, and HNO3 Using Density Functional Theory-Based Molecular Dynamics Simulations

Abstract

In this study we investigate the free energy barrier associated with the dissociation of strong acids, XH (HBr, HCl and HNO3) deprotonation, and subsequent formation of ionpairs, X–___H3O+ in the vicinity of the air-water interface. We will show that the free energy for acid dissociation for HCl and HNO3 show significant differences at the air-water than under bulk solvation conditions producing a picture where at the interface associated molecular species can be stable. For the strongest acid we consider, HBr the more traditional picture of acids is preserved in the vicinity of the air-water interface. Our results have implications for our understanding of acids, and their surface tensions at the air-water interface.

Revised: June 25, 2015 | Published: December 18, 2014

Citation

Baer M., D.J. Tobias, and C.J. Mundy. 2014. Investigation of Interfacial and Bulk Dissociation of HBr, HCl, and HNO3 Using Density Functional Theory-Based Molecular Dynamics Simulations. Journal of Physical Chemistry C 118, no. 50:29412-29420. PNNL-SA-103497. doi:10.1021/jp5062896