Impact of electron-phonon interaction on the electronic structure of interfaces between organic molecules and a MoS$_2$ monolayer

TL;DR

This study uses first-principles calculations to analyze how electron-phonon interactions affect the electronic properties of MoS₂ interfaces with organic molecules, revealing significant band-gap renormalization and molecular vibrational effects.

Contribution

It provides a detailed first-principles analysis of electron-phonon effects on hybrid MoS₂-organic interfaces, highlighting temperature-dependent band structure changes and vibrational satellite features.

Findings

Band-gap renormalization of ~80 meV due to zero-point vibrations.

Molecular vibrational satellites observed in spectral functions.

Hybrid character of pyridine vibrational satellites.

Abstract

By means of first-principles calculations, we investigate the role of electron-phonon interaction in the electronic structure of hybrid interfaces, formed by MoS$_2$ and monolayers of the organic molecules pyrene and pyridine, respectively. Quasiparticle energies are initially obtained within the $G_0W_0$ approximation and subsequently used to evaluate the electron-phonon self-energy and momentum-resolved spectral functions to assess the temperature renormalization of the band structure. We find that the band-gap renormalization by zero-point vibrations of both hybrid systems is comparable to that of pristine MoS$_2$, with a value of approximately 80 meV. Pronounced features of molecular origin emerge in the spectral function of the valence region, which we attribute to satellites arising from out-of-plane vibrational modes of the organic monolayers. For pyrene, this satellite exhibits a predominantly molecular character, while for pyridine, it has a hybrid nature, originating from the coupling of molecular vibrations to the MoS$_2$ valence band.