Kohn-Sham potential for a strongly correlated finite system with fractional occupancy

Autor: Cesar Ramon Proetto, A. Benítez
Rok vydání: 2016
Předmět:
Zdroj: Physical Review A. 94
ISSN: 2469-9934
2469-9926
Popis: Using a simplified one-dimensional model of a diatomic molecule, the associated interacting density and corresponding Kohn-Sham (KS) potential have been obtained analytically for all fractional molecule occupancies $N$ between 0 and 2. For the homonuclear case, and in the dissociation limit, the exact Kohn-Sham potential builds a barrier at the midpoint between the two atoms, whose strength increases linearly with $N$, with $1lN\ensuremath{\le}2$. In the heteronuclear case, the dissociating KS potential besides the barrier also exhibits a plateau around the atom with the higher ionization potential, whose size (but not its strength) depends on $N$. An anomalous zero-order scaling of the Kohn-Sham potential with regards to the strength of the electron-electron repulsion is clearly displayed by our model; without this property both the unusual barrier and the plateau features will be absent.
Databáze: OpenAIRE