Surface relaxation and ferromagnetism of Rh(001)

TL;DR

This study uses density functional theory to analyze the surface relaxation and potential ferromagnetism of Rh(001), resolving discrepancies between previous calculations and experiments by considering free energy effects.

Contribution

It demonstrates that including free energy considerations in DFT calculations aligns theoretical results with experimental observations for Rh(001) surface relaxation.

Findings

DFT results agree with experiments when free energy is considered

Surface thermal expansion is analyzed

Potential surface magnetism is investigated

Abstract

The significant discrepancy between first-principles calculations and experimental analyses for the relaxation of the (001) surface of rhodium has been a puzzle for some years. In this paper we present density functional theory calculations using the local-density approximation and the generalized gradient approximation of the exchange-correlation functional. We investigate the thermal expansion of the surface and the possibility of surface magnetism. The results throw light on several, hitherto overlooked, aspects of metal surfaces. We find, that, when the free energy is considered, density-functional theory provides results in good agreement with experiments.