Regensburg 2019 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 58: Focus Session: Electron-Phonon Interactions II

O 58.5: Vortrag

Mittwoch, 3. April 2019, 16:15–16:30, H15

Simulation of electronic friction effects in chemical dynamics at metal surfaces: Understanding the successes and failures of ab-initio methods — •Connor Box and Reinhard J. Maurer — Department of Chemistry, University of Warwick, United Kingdom

The coupling of molecular adsorbate motion with hot electrons in a metal substrate represents a breakdown of the Born-Oppenheimer approximation with measurable consequences. An accurate theoretical description of how these hot electron effects modify the reaction dynamics of molecules on metals will be essential to utilize light-matter interaction in catalysis. The electron-phonon coupling between adsorbate vibrations and hot electrons are efficiently described in a density functional theory-based molecular dynamics with electronic friction (MDEF) approach, where electronic friction forces act on atoms within a Langevin framework. [1] Several methods have been proposed to describe electronic friction; however, more work remains to be done to provide a transferable and accurate description of experimental findings. In this talk, we present our efforts towards pushing beyond the current limitations of the MDEF method. We explore the consequences of existing approximations in MDEF calculations for the frequently studied carbon monoxide adsorbed Cu(100) and Pt(111) surfaces. [2] We systematically assess the importance of substrate motion, vibrational anharmonicity, and mode coupling in comparison with recently published many-body perturbation theory results [3] to guide future directions of method development. [1] PRL 116, 217601 (2016), [2] PRB 94, 115432 (2016), [3] PRL 120, 156804 (2018)