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arXiv · 2002.02808

Ab initio Description of Bond-Breaking in Large Electric Fields

Michael Ashton·Arpit Mishra·Joerg Neugebauer·Christoph Freysoldt
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Abstract

Strong ($10^{10}$ V/m) electric fields capable of inducing atomic bond-breaking represent a powerful tool for surface chemistry. However, their exact effects are difficult to predict due to a lack of suitable tools to probe their associated atomic-scale mechanisms. Here we introduce a generalized dipole correction for charged repeated-slab models that controls the electric field on both sides of the slab, thereby enabling direct theoretical treatment of field-induced bond-breaking events. As a prototype application, we consider field evaporation from a kinked W surface. We reveal two qualitatively different desorption mechanisms that can be selected by the magnitude of the applied field.

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Michael Ashton, Arpit Mishra, Joerg Neugebauer, Christoph Freysoldt. 2020-02-07. Ab initio Description of Bond-Breaking in Large Electric Fields. https://doi.org/10.1103/physrevlett.124.176801

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