Adsorbate Interactions of CO Chemisorbed on Pt(111)

TL;DR

This paper explains the repulsive interactions between CO molecules on Pt(111) surfaces through a model coupling Pt--CO separation with substrate coordinates, successfully reproducing observed interaction ranges and vibrational decay behaviors.

Contribution

It introduces a novel model linking CO-Pt separation to substrate coordinates to explain adsorbate interactions and vibrational decay on Pt(111).

Findings

Reproduces the long-range repulsive interactions.

Matches experimental vibrational decay magnitudes.

Explains non-monotonic distance dependence.

Abstract

We show that the observed repulsive interaction between CO molecules on the Pt(111) surface can be explained by the coupling of the Pt--CO separation with Pt-Pt coordinates in the substrate. The observed long range of the interaction and the non-monotonic distance dependence are reproduced. The magnitude of the multiphonon decay of the Pt--CO vibration calculated in this model is also in agreement with experiment.