Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 100: Surface Dynamics II

O 100.9: Vortrag

Freitag, 4. April 2014, 12:30–12:45, PHY C 213

Vibrational properties of alkali nitrate solutions: from clusters to the water/vapor interface — •Gang Huang¹, Marie-Pierre Gaigeot², and Marialore Sulpizi¹ — ¹Institute for physics, Johannes Gutenberg University, Staudingerweg 7,55099, Mainz, Germany — ²LAMBE UMR8587, University of Evry Val d’Essonne, Blvd F. Mitterrand, Bat Maupertuis, 91025 EVRY, France

The structure of ions at the vapor/aqueous interface, as well as their influence on the water’s hydrogen bond network is of special interest to the atmospheric chemistry community. We use Density Functional Theory-based molecular dynamics to investigate the structure and dynamics of solvated alkali nitrate in water clusters and at the vapor-aqueous interface.

Vibrational density of states (VDOS) are calculated to extract the vibrational signatures for the ions and the surrounding water molecules. We find that in the clusters alkali-nitrate induces a redshift of hydrogen-bonded O-H stretch peaks while in the full water/vapor interface there is an overall blueshift of the hydrogen bonded OH-stretching band. Results are rationalized in term of contact vs water separated ion pairs and confronted with recent surface specific vibrational spectroscopy experiments [1].

[1]A. M. Jubb, W. Hua, and H. Allen, Ann. Rev. Phys. Chem. 63, 107 (2012)