Cargando…

Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements

Is there a correlation between the (hetero)aromaticity of the core of a molecule and its conductance in a single molecular junction? To address this question, which is of fundamental interest in molecular electronics, oligo(arylene-ethynylene) (OAE) molecular wires have been synthesized with core un...

Descripción completa

Detalles Bibliográficos
Autores principales: Gantenbein, Markus, Wang, Lin, Al-jobory, Alaa A., Ismael, Ali K., Lambert, Colin J., Hong, Wenjing, Bryce, Martin R.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5431762/
https://www.ncbi.nlm.nih.gov/pubmed/28496118
http://dx.doi.org/10.1038/s41598-017-01903-0
_version_ 1783236496612917248
author Gantenbein, Markus
Wang, Lin
Al-jobory, Alaa A.
Ismael, Ali K.
Lambert, Colin J.
Hong, Wenjing
Bryce, Martin R.
author_facet Gantenbein, Markus
Wang, Lin
Al-jobory, Alaa A.
Ismael, Ali K.
Lambert, Colin J.
Hong, Wenjing
Bryce, Martin R.
author_sort Gantenbein, Markus
collection PubMed
description Is there a correlation between the (hetero)aromaticity of the core of a molecule and its conductance in a single molecular junction? To address this question, which is of fundamental interest in molecular electronics, oligo(arylene-ethynylene) (OAE) molecular wires have been synthesized with core units comprising dibenzothiophene, carbazole, dibenzofuran and fluorene. The biphenyl core has been studied for comparison. Two isomeric series have been obtained with 4-ethynylpyridine units linked to the core either at para-para positions (para series 1–5) or meta-meta positions (meta series 6–10). A combined experimental and computational study, using mechanically controlled break junction measurements and density functional theory calculations, demonstrates consistently higher conductance in the para series compared to the meta series: this is in agreement with increased conjugation of the π–system in the para series. Within the para series conductance increases in the order of decreasing heteroaromaticity (dibenzothiophene < carbazole < dibenzofuran). However, the sequence is very different in the meta series, where dibenzothiophene ≈ dibenzofuran < carbazole. Excellent agreement between theoretical and experimental conductance values is obtained. Our study establishes that both quantum interference and heteroaromaticity in the molecular core units play important and inter-related roles in determining the conductance of single molecular junctions.
format Online
Article
Text
id pubmed-5431762
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-54317622017-05-16 Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements Gantenbein, Markus Wang, Lin Al-jobory, Alaa A. Ismael, Ali K. Lambert, Colin J. Hong, Wenjing Bryce, Martin R. Sci Rep Article Is there a correlation between the (hetero)aromaticity of the core of a molecule and its conductance in a single molecular junction? To address this question, which is of fundamental interest in molecular electronics, oligo(arylene-ethynylene) (OAE) molecular wires have been synthesized with core units comprising dibenzothiophene, carbazole, dibenzofuran and fluorene. The biphenyl core has been studied for comparison. Two isomeric series have been obtained with 4-ethynylpyridine units linked to the core either at para-para positions (para series 1–5) or meta-meta positions (meta series 6–10). A combined experimental and computational study, using mechanically controlled break junction measurements and density functional theory calculations, demonstrates consistently higher conductance in the para series compared to the meta series: this is in agreement with increased conjugation of the π–system in the para series. Within the para series conductance increases in the order of decreasing heteroaromaticity (dibenzothiophene < carbazole < dibenzofuran). However, the sequence is very different in the meta series, where dibenzothiophene ≈ dibenzofuran < carbazole. Excellent agreement between theoretical and experimental conductance values is obtained. Our study establishes that both quantum interference and heteroaromaticity in the molecular core units play important and inter-related roles in determining the conductance of single molecular junctions. Nature Publishing Group UK 2017-05-11 /pmc/articles/PMC5431762/ /pubmed/28496118 http://dx.doi.org/10.1038/s41598-017-01903-0 Text en © The Author(s) 2017 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Gantenbein, Markus
Wang, Lin
Al-jobory, Alaa A.
Ismael, Ali K.
Lambert, Colin J.
Hong, Wenjing
Bryce, Martin R.
Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title_full Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title_fullStr Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title_full_unstemmed Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title_short Quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
title_sort quantum interference and heteroaromaticity of para- and meta-linked bridged biphenyl units in single molecular conductance measurements
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5431762/
https://www.ncbi.nlm.nih.gov/pubmed/28496118
http://dx.doi.org/10.1038/s41598-017-01903-0
work_keys_str_mv AT gantenbeinmarkus quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT wanglin quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT aljoboryalaaa quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT ismaelalik quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT lambertcolinj quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT hongwenjing quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements
AT brycemartinr quantuminterferenceandheteroaromaticityofparaandmetalinkedbridgedbiphenylunitsinsinglemolecularconductancemeasurements