SIMONE PEZZOTTI

PhD research (2015-2018)

My PhD project, funded by ANR-DYNAWIN, focuses on the characterization of aqueous interfaces by combining DFT based molecular dynamics (DFT-MD) simulations and vibrational Sum Frequency Generation Spectroscopy (vSFG).

A new universal methodology has been developed in synergy between DFT-MD simulations and vSFG spectroscopy to disentangle second and third order contributions to vSFG, arising from different water layers at charged aqueous interfaces, fully ab-initio on the basis of water structural properties only.

Thanks to this universal procedure, a correct interpretation of vSFG spectra can be achieved and the thickness of the interfacial regions probed in the experiments unravelled.^1,2

With a first application of our methodology to air-water interfaces, a specific interfacial H-Bonds structure has been discovered at the water surface: a 2-Dimensional H-Bond Network (2DN)³. The existence of the 2DN structure allows the rationalization of specific chemical and physical properties at planar and non-planar (water droplets) air-water interfaces, like surface tension, surface potential, atypical proton hopping mechanism, ions absorption, spectroscopic properties to cite a few^3,4,5.

These findings have been generalized and the 2DN structure has been found to be systematically the stable water arrangement at the interface with hydrophobic surfaces/media, with water thus exhibiting similar structural and dynamical properties at all such interfaces. This is currently under papers being written up and submitted.  

Method: DFT-based molecular dynamics simulations. 

Superviseur

• Prof. Marie-Pierre Gaigeot

Financement 

• ANR DYNAWIN

Ecole doctorale

• Lien vers ED saclay

Inside the group with Daria R. Galimberti (Post-Doc, ANR DYNAWIN), Falvio Siro Brigiano (PhD), Fabrizio Creazzo (PhD, LABEX CHARM₃AT), Louis Potier (PhD, ANR SLIMCAT), Sana Bougueroua (PhD , LABEX CHARM₃AT UVSQ-UEVE & now Engineer in Informatics)

1. Pezzotti, S.; Galimberti, D. R.; Shen, Y. R.,  Gaigeot, M.-P. Phys. Chem. Chem. Phys., 10.1039/C7CP06110B
2. Pezzotti, S.; Galimberti, D. R.; Shen, Y. R.,  Gaigeot, M.-P. submitted to J. Phys. Chem. C  (2018)
3. Pezzotti, S.; Galimberti, D. R.; Gaigeot, M.-P. ,  J. Phys. Chem. Lett. 2017, 8, 3133–3141
4. Pezzotti, S.; Serva, A.;  Gaigeot, M.-P. J. Mol. Struct. (2018)
5. Pezzotti, S.; Serva, A.; Bougueroua, S.;  Gaigeot, M.-P. J. Chem. Phys. (2018)