Frontier orbitals control dynamical disorder in molecular semiconductors

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Neef, Alexander, Hammer, Sebastian, Yao, Yuxuan, Sharma, Shubham, Beaulieu, Samuel, Dong, Shuo, Pincelli, Tommaso, Frank, Maximillian, Wolf, Martin, Rossi, Mariana, Oberhofer, Harld, Rettig, Laurenz, Pflaum, Jens, Ernstorfer, Ralph
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916513411235840
author Neef, Alexander
Hammer, Sebastian
Yao, Yuxuan
Sharma, Shubham
Beaulieu, Samuel
Dong, Shuo
Pincelli, Tommaso
Frank, Maximillian
Wolf, Martin
Rossi, Mariana
Oberhofer, Harld
Rettig, Laurenz
Pflaum, Jens
Ernstorfer, Ralph
author_facet Neef, Alexander
Hammer, Sebastian
Yao, Yuxuan
Sharma, Shubham
Beaulieu, Samuel
Dong, Shuo
Pincelli, Tommaso
Frank, Maximillian
Wolf, Martin
Rossi, Mariana
Oberhofer, Harld
Rettig, Laurenz
Pflaum, Jens
Ernstorfer, Ralph
contents Charge transport in organic semiconductors is limited by dynamical disorder. Design rules for new high-mobility materials have therefore focused on limiting its two foundations: structural fluctuations and the transfer integral gradient. However, it has remained unclear how these goals should be translated into molecular structures. Here we show that a specific shape of the frontier orbital, with a lack of nodes along the long molecular axis, reduces the transfer integral gradient and therefore the dynamical disorder. We investigated single crystals of the prototypical molecular semiconductors pentacene and picene by angle-resolved photoemission spectroscopy and dynamical disorder calculations. We found that picene exhibits a remarkably low dynamical disorder. By separating in- and out-of-plane components of dynamical disorder, we identify the reason as a reduced out-of-plane disorder from a small transfer integral derivative. Our results demonstrate that molecules with an armchair $π$-electron topology and same-phase frontier orbitals like picene are promising molecular building blocks for the next generation of organic semiconductors.
format Preprint
id arxiv_https___arxiv_org_abs_2412_06030
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Frontier orbitals control dynamical disorder in molecular semiconductors
Neef, Alexander
Hammer, Sebastian
Yao, Yuxuan
Sharma, Shubham
Beaulieu, Samuel
Dong, Shuo
Pincelli, Tommaso
Frank, Maximillian
Wolf, Martin
Rossi, Mariana
Oberhofer, Harld
Rettig, Laurenz
Pflaum, Jens
Ernstorfer, Ralph
Materials Science
Disordered Systems and Neural Networks
Charge transport in organic semiconductors is limited by dynamical disorder. Design rules for new high-mobility materials have therefore focused on limiting its two foundations: structural fluctuations and the transfer integral gradient. However, it has remained unclear how these goals should be translated into molecular structures. Here we show that a specific shape of the frontier orbital, with a lack of nodes along the long molecular axis, reduces the transfer integral gradient and therefore the dynamical disorder. We investigated single crystals of the prototypical molecular semiconductors pentacene and picene by angle-resolved photoemission spectroscopy and dynamical disorder calculations. We found that picene exhibits a remarkably low dynamical disorder. By separating in- and out-of-plane components of dynamical disorder, we identify the reason as a reduced out-of-plane disorder from a small transfer integral derivative. Our results demonstrate that molecules with an armchair $π$-electron topology and same-phase frontier orbitals like picene are promising molecular building blocks for the next generation of organic semiconductors.
title Frontier orbitals control dynamical disorder in molecular semiconductors
topic Materials Science
Disordered Systems and Neural Networks
url https://arxiv.org/abs/2412.06030