Molecular dynamics simulations of structure and vibrational spectroscopy at surfaces of aqueous salt solutions

COLL 381

Douglas J. Tobias1, Eric Brown2, Pavel Jungwirth3, and Martin Mucha3. (1) Department of Chemistry, University of California, Irvine, CA 92697-2025, (2) Department of Chemistry, University of California, Irvine, Irvine, CA 92697, (3) J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejskova 3, 182 23 Prague 8, Czech Republic
The surfaces of aqueous ionic solutions have traditionally been regarded as devoid of ions. Molecular dynamics simulations have recently predicted that polarizable anions adsorb to the air/water interface. The presence of ions at aqueous interfaces has implications for the heterogeneous chemistry of aqueous aerosol particles in the atmosphere. This prediction has led to several experimental investigations. This talk will survey the simulation and experimental results, with a focus on vibrational spectroscopy. Vibrational sum frequency generation spectra of water at salt solution/air interfaces computed from molecular dynamics simulations will be compared to experimental data to confirm the predictions of the simulations, as well as to provide insight into the interpretation of the spectra in terms of the interfacial structure.