Surface-specific spectroscopy from first principles

Next BIU Engineering Colloquium,
Dr. Yair Litman, Tuesday, 6.2.24 @14:00

BIU Engineering Building 1103, Room 329

Via Zoom: https://biu-ac-il.zoom.us/j/2783383494?omn=88509218054

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We are delighted to host

Dr. Yair Litman

University of Cambridge

Dr. Litman will give a talk on the subject:

Surface-specific spectroscopy from first principles

Abstract: Our current understanding of the structure and dynamics of aqueous interfaces at the molecular level has grown substantially in the last few decades due to the continuous development of surface-specific spectroscopies, such as vibrational sum-frequency generation (VSFG). While VSFG provides valuable information on its own, only when it is combined with accurate atomistic simulations can a comprehensive microscopic picture emerge. In the first part of my talk, I will present our recent efforts towards the simulation of surface-specific spectroscopies from first principles using machine learning approaches [1]. Next, I will focus on the liquid/air interface of different aqueous electrolyte solutions [2]. I will clearly demonstrate that the textbook electric-double layer model is an incomplete microscopic picture to understand the interface of NaI, NaBr, NaCl, and NaF aqueous solutions and it is completely inappropriate for the NaOH and CsF cases. Based on our first principles simulations, we propose that the surface of most common electrolytes solutions is stratified into two water layers, one depleted and the other enriched with ions, creating an effective liquid-liquid interface buried a few Å inside the solution.

[1] Y. Litman, J. Lan, Y Nagata, D. M. Wilkins, J. Phys. Chem. Lett. 14,  8175-8182 (2023)

[2] Y. Litman, K-Y. Chiang, T. Seki, Y. Nagata, M. Bonn,  accepted, Nat. Chem. (2023)

Short bio: Yair Litman received his diploma from the University of Buenos Aires in 2014. Shortly after, he worked with Professor Daniel Laria where he was introduced to path integral methods to study isotope fractionation in hydrogen halides in water clusters. At the end of 2016, he started his PhD at the Fritz Haber Institute in Berlin, under the supervision of Dr Mariana Rossi, where he investigated the impact of nuclear quantum effects in equilibrium and dynamical properties of H-bonded systems composed of water and organic molecules adsorbed on inorganic surfaces. He finished his PhD in 2020 and since then has been working on theoretical and method development of non-adiabatic rate theories and non-linear spectroscopies such as tip-enhanced Raman and sum-frequency generation at the Max Planck for Structure and Dynamics of Matter (Hamburg, Rossi Group), Max Planck Institute for Polymer Research (Mainz, Bonn Group), and the University of Cambridge (Althorpe Group), where he is based currently as a DFG Walter Benjamin fellow.