Charging of Cu atom on Mo supported thin films of ScN, MgO and NaF

TL;DR

This study uses density functional theory to analyze how Cu atoms acquire charge when supported on Mo with thin films of ScN, MgO, and NaF, revealing the importance of weak interactions and surface distortions.

Contribution

It provides new insights into the charge transfer mechanisms at metal/film interfaces, highlighting the role of surface deformations and weak interactions in adatom charging.

Findings

Charge transfer occurs from the interface to Cu adatoms.

Weak metal-film interactions facilitate adatom charging.

NaF film distortion is anharmonic and coupled to charge redistribution.

Abstract

Molybdenum supported thin films of ScN, MgO and NaF with a Cu adatom have been studied in the framework of density functional theory. We have observed a charge transfer from the metal/film interface to the Cu atom and investigated its relation to surface and interface deformations. We find that a weak interaction between the metal and the film is a promising prerequisite for adatom charging. The detailed study of Cu/NaF/Mo and NaF/Mo indicates that the distortion of the NaF film caused by the Cu adsorption has essentially anharmonic character, as it is coupled to a strong charge redistribution in the system.