Orbital tomography of hybridized and dispersing molecular overlayers

TL;DR

This study combines photoemission experiments and calculations to analyze how pentacene monolayers behave on different metal surfaces, revealing substrate effects on molecular orbitals and their dispersion.

Contribution

It provides a detailed comparison of molecular orbital behavior on Ag(110) and Cu(110), demonstrating substrate-induced changes and a method to simulate photoemission intensity in extended systems.

Findings

Orbitals are molecule-like on Ag(110)

Strong dispersion observed on Cu(110)

Photoemission intensity can be simulated effectively

Abstract

With angle resolved photoemission experiments and \emph{ab-initio} electronic structure calculations, the pentacene monolayers on Ag(110) and Cu(110) are compared and contrasted allowing the molecular orientation and an unambiguous assignment of emissions to specific orbitals to be made. On Ag(110), the orbitals remain essentially isolated-molecule like, while strong substrate-enhanced dispersion and orbital modification are observed upon adsorption on Cu(110). We show how the photoemission intensity of extended systems can be simulated and that it behaves essentially like that of the isolated molecule modulated by the band dispersion due to intermolecular interactions.