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Non-Adiabatic Potential-Energy Surfaces by Constrained Density-Functional Theory

Joerg Behler·Bernard Delley·Karsten Reuter·Matthias Scheffler
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Abstract

Non-adiabatic effects play an important role in many chemical processes. In order to study the underlying non-adiabatic potential-energy surfaces (PESs), we present a locally-constrained density-functional theory approach, which enables us to confine electrons to sub-spaces of the Hilbert space, e.g. to selected atoms or groups of atoms. This allows to calculate non-adiabatic PESs for defined charge and spin states of the chosen subsystems. The capability of the method is demonstrated by calculating non-adiabatic PESs for the scattering of a sodium and a chlorine atom, for the interaction of a chlorine molecule with a small metal cluster, and for the dissociation of an oxygen molecule at the Al(111) surface.

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Joerg Behler, Bernard Delley, Karsten Reuter, Matthias Scheffler. 2006-11-29. Non-Adiabatic Potential-Energy Surfaces by Constrained Density-Functional Theory. https://doi.org/10.1103/physrevb.75.115409

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