Strain-Dependence of Surface Diffusion: Ag on Ag(111) and Pt(111)

TL;DR

This study uses density-functional theory to analyze how surface diffusion barriers for silver vary with strain on different substrates, explaining experimentally observed reconstructions.

Contribution

It provides a detailed computational analysis of strain-dependent surface diffusion barriers for Ag on various substrates, elucidating the conditions for surface reconstruction.

Findings

Diffusion barrier for Ag on Ag(111) increases linearly with lattice constant.

Strain influences surface reconstruction only after two Ag layers are deposited.

Theoretical results explain experimental observations of Ag surface behavior.

Abstract

Using density-functional theory with the local-density approximation and the generalized gradient approximation we compute the energy barriers for surface diffusion for Ag on Pt(111), Ag on one monolayer of Ag on Pt(111), and Ag on Ag(111). The diffusion barrier for Ag on Ag(111) is found to increase linearly with increasing lattice constant. We also discuss the reconstruction that has been found experimentally when two Ag layers are deposited on Pt(111). Our calculations explain why this strain driven reconstruction occurs only after two Ag layers have been deposited.