This talk is dedicated to probing the microscopic structural organization of silica-water interfaces including electrolytes by first principles DFT-based molecular dynamics simulations (DFT-MD). Ions from electrolytic solutions play key roles on interfacial water/mineral interfaces: their adsorption typically drives pollutant transport in groundwater, mineral dissolution, clay swelling, and electrolytes can strongly affect the binding of organic molecules because of competitive interactions. We will present our very recent DFT-MD simulations of electrolytic silica/water interfaces (electrolytes are KCl, NaCl, NaI) in order to unravel the structural properties of electrolytes at the crystalline quartz/liquid water interface and at the amorphous silica/liquid water interface. A detailed analysis of the non-linear SFG spectral signatures of these electrolytic silica/water interfaces is presented, comparisons between the different mineral/water interfaces allow us to definitely conclude on how the structural arrangements of liquid water at these electrolytic interfaces modulate the final spectroscopic signatures. Generalization of the SFG signatures to other mineral/water interfaces can be done. Works performed by Morgane Pfeiffer-Laplaud (PhD), Simone Pezzotti (PhD), Fabrizio Creazzo (PhD). Recent Publications: J.Phys.Chem.Letters 7 :3229(2016) ; J.Phys.Chem.C. 120 :4866 (2016) ; J.Phys.Chem.C. 119 :27354 (2016) ;

Silica/water interfaces investigated by DFT-MD simulations: Structure and SFG spectroscopy revealed in detail

253rd National Meeting (2017)

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