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Title: Intermediate polaronic charge transport in organic crystals from a many-body first-principles approach
Abstract

Charge transport in organic molecular crystals (OMCs) is conventionally categorized into two limiting regimes − band transport, characterized by weak electron-phonon (e-ph) interactions, and charge hopping due to localized polarons formed by strong e-ph interactions. However, between these two limiting cases there is a less well understood intermediate regime where polarons are present but transport does not occur via hopping. Here we show a many-body first-principles approach that can accurately predict the carrier mobility in this intermediate regime and shed light on its microscopic origin. Our approach combines a finite-temperature cumulant method to describe strong e-ph interactions with Green-Kubo transport calculations. We apply this parameter-free framework to naphthalene crystal, demonstrating electron mobility predictions within a factor of 1.5−2 of experiment between 100 and 300 K. Our analysis reveals the formation of a broad polaron satellite peak in the electron spectral function and the failure of the Boltzmann equation in the intermediate regime.

Authors:
; ; ;
Publication Date:
NSF-PAR ID:
10376864
Journal Name:
npj Computational Materials
Volume:
8
Issue:
1
ISSN:
2057-3960
Publisher:
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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