# Platinum atomic contacts: from tunneling to contact

## TL;DR

This paper provides a detailed theoretical analysis of electronic transport in platinum nanocontacts, emphasizing the importance of technical details like system size and basis set choice in accurately modeling tunneling and contact regimes.

## Contribution

It highlights the critical influence of system size and basis set selection on tunneling conductance calculations in platinum nanocontacts, offering practical recommendations for accurate modeling.

## Key findings

- Proper system size prevents unphysical charge oscillations.
- Large-cutoff-radius basis sets improve conductance decay modeling.
- Technical details have minimal impact in the contact regime.

## Abstract

We present a theoretical study of the electronic transport through Pt nanocontacts. We show that the analysis of the tunnelling regime requires a very careful treatment of the technical details. For instance, an insufficient size of the system can cause unphysical charge oscillations to arise along the transport direction; moreover, the use of an inappropriate basis set can deviate the distance dependence of the conductance from the expected exponential trend. While the conductance decay can be either corrected by employing ghost atoms or a large-cutoff-radius basis set, the same does not apply to the corrugation, for which only the second option is recommended. Interestingly, these details were not found to have a remarkable impact in the contact regime. These findings are important for theoretical studies of distance-dependent phenomena in scanning-probe and break-junction experiments.