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Protonation tuning of quantum interference in azulene-type single-molecule junctions.

ABSTRACT: The protonation of azulene derivatives with quantum interference effects is studied by the conductance measurements of single-molecule junctions. Three azulene derivatives with different connectivities are synthesized and reacted with trifluoroacetic acid to form the protonated states. It is found that the protonated azulene molecular junctions produce more than one order of magnitude higher conductance than the neutral states, while the molecules with destructive interference show more significant changes. These experimental observations are supported by our recently-developed parameter free theory of connectivity, which suggests that the largest conductance change occurs when destructive interference near the Fermi energy in the neutral state is alleviated by protonation.

SUBMITTER: Yang G

PROVIDER: S-EPMC5676185 | biostudies-other | 2017 Nov

REPOSITORIES: biostudies-other

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Protonation tuning of quantum interference in azulene-type single-molecule junctions.

Yang Guogang G Sangtarash Sara S Liu Zitong Z Li Xiaohui X Sadeghi Hatef H Tan Zhibing Z Li Ruihao R Zheng Jueting J Dong Xiaobiao X Liu Junyang J Yang Yang Y Shi Jia J Xiao Zongyuan Z Zhang Guanxin G Lambert Colin C Hong Wenjing W Zhang Deqing D

Chemical science 20170907 11

The protonation of azulene derivatives with quantum interference effects is studied by the conductance measurements of single-molecule junctions. Three azulene derivatives with different connectivities are synthesized and reacted with trifluoroacetic acid to form the protonated states. It is found that the protonated azulene molecular junctions produce more than one order of magnitude higher conductance than the neutral states, while the molecules with destructive interference show more signific ...[more]

PMID: 29163904

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