A Green's Function Approach for Determining Surface Induced Broadening and Shifting of Molecular Energy Levels

Publikation: Bidrag til tidsskriftTidsskriftartikelfagfællebedømt

Upon adsorption of a molecule onto a surface, the molecular energy levels (MELs) broaden and change their alignment. This phenomenon directly affects electron transfer across the interface and is, therefore, a fundamental observable that influences electrochemical device performance. Here, we propose a rigorous parameter-free framework, built upon the theoretical construct of Green's functions, for studying the interface between a molecule and a bulk surface and its effect on MELs. The method extends beyond the usual wide-band limit approximation, and its generality allows its use with any level of electronic structure theory. We demonstrate its ability to predict the broadening and shifting of MELs as a function of intramolecular coupling, molecule/surface coupling, and the surface density of states for a molecule with two MELs adsorbed on a one-dimensional model metal surface. The new approach could help provide guidelines for the design and experimental characterization of electrochemical devices with optimal electron transport.

OriginalsprogEngelsk
TidsskriftNano Letters
Vol/bind22
Udgave nummer24
Sider (fra-til)9854–9860
Antal sider7
ISSN1530-6984
DOI
StatusUdgivet - 2022

ID: 332197572