Model potential for the description of metal/organic interface states

TL;DR

This paper introduces an analytical one-dimensional model potential that predicts electronic interface states at metal/organic interfaces, accurately matching experimental data without free parameters.

Contribution

The model uses graphene as a universal representation of organic adlayers and systematically relates interface state energies to bond distances, demonstrating broad applicability.

Findings

Accurately predicts interface state energies across various systems

Shows systematic dependence of energy on bond distance

Matches experimental results without free fitting parameters

Abstract

We present an analytical one-dimensional model potential for the description of electronic interface states that form at the interface between a metal surface and flat-lying adlayers of $\pi$-conjugated organic molecules. The model utilizes graphene as a universal representation of these organic adlayers. It predicts the energy position of the interface state as well as the overlap of its wave function with the bulk metal without free fitting parameters. We show that the interface state's energy depends systematically on the bond distance between the carbon backbone of the adayers and the metal. The general applicability and robustness of the model is demonstrated by a comparison of the calculated energies with numerous experimental results for a number of flat-lying organic molecules on different closed-packed metal surfaces that cover a large range of bond distances.