Adsorption of Xe atoms on metal surfaces: New insights from first-principles calculations

TL;DR

This study uses first-principles density-functional theory calculations to reveal that Xe atoms prefer on-top sites over hollow sites on various metal surfaces, challenging traditional assumptions about weak adsorption.

Contribution

It provides new insights into the site preference of Xe atoms on metal surfaces by identifying polarization and Pauli repulsion as key factors, using advanced computational methods.

Findings

Xe prefers on-top sites on all studied metal surfaces

Polarization and Pauli repulsion influence site preference

Challenges traditional assumptions about weak adsorption

Abstract

The adsorption of rare gases on metal surfaces serve as the paradigm of weak adsorption where it is typically assumed that the adsorbate occupies maximally coordinated hollow sites. Density-functional theory calculations using the full-potential linearized augmented plane wave method for Xe adatoms on Mg(0001), Al(111), Ti(0001), Cu(111), Pd(111), and Pt(111), show, however, that Xe prefers low-coordination on-top sites in all cases. We identify the importance of polarization and a site-dependent Pauli repulsion in actuating the site preference and the principle nature of the rare-gas atom--metal surface interaction.