Water structure and dynamics at the solid/liquid interface from ab initio simulations

• Applicant: Professorin Dr. Marialore Sulpizi
• Subject Area: Theoretical Chemistry: Molecules, Materials, Surfaces ; Physical Chemistry of Solids and Surfaces, Material Characterisation ; Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 239238969

• Final Report Year: 2018

Final Report Abstract

Molecular properties at interfaces may be quite different from bulk properties, and this for both the solid and liquid meeting at an interface. In this research project we aimed to address structure, dynamics and vibrational properties of solid/liquid interfaces, with particular focus on the calcium fluorite/ water interface. The project had a dual aspect of fundamental and applied science. On one side, we aimed to develop new tools to characterize properties at interfaces and, on the other, to apply our newly developed methodologies to a system of technological and industrial interest, namely calcium fluorite. Calcium fluorite is, indeed, often used as an analogous of UO2 in dissolution experiments and to understand the longterm dissolution behavior of spent nuclear fuel. In carrying on our research project we have been closely collaborating with the experimental group of Dr. E. H. G. Backus and Prof. M. Bonn at the Max Planck Institute for Polymer Research (MPIP) in Mainz. In parallel with the development of our theoretical/ computational study, they have measured the surface sensitive vibrational spectra of the CaF2 / water interface using Sum Frequency Generation spectroscopy (SFG). The close interplay between the complementary computational and experimental approaches has permitted to shed new light on the microscopic ordering of the liquid at the interface with a solid as function of surface protonation/charge state. Moreover, it has also permitted to elucidate the microscopic/ molecular details behind the energy relaxation at the interface.

Publications

• Microscopic Insights into the Fluorite/Water Interfaces from Vibrational Sum Frequency Generation Spectroscopy. High Performance Computing in Science and Engineering 16, 131-143
  R Khatib, M Sulpizi
  
• Molecular dynamics simulations of SFG librational modes spectra of water at the waterair interface. The Journal of Physical Chemistry C 120 (33), 18665-18673
  R Khatib, T Hasegawa, M Sulpizi, EHG Backus, M Bonn, Y Nagata
  
• Sum Frequency Generation Spectra from Velocity-Velocity correlation Functions. The Journal of Physical Chemistry Letters 8 (6), 1310-1314
  Remi Khatib and M. Sulpizi
  
• Water orientation and hydrogen-bond structure at the fluorite/water interface. Scientific Reports 6, 24287
  R Khatib, EHG Backus, M Bonn, MJ Perez-Haro, MP Gaigeot, M Sulpizi
  
• (2015): The Fluorite/Water Interfaces: Structure and Spectroscopy from First Principles Simulations. In: Wolfgang E. Nagel, Dietmar H. Kröner und Michael M. Resch (Hg.): High Performance Computing in Science and Engineering ‘14. Cham: Springer Internation
  R Khatib, M Sulpizi