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Substituent Control of σ-Interference Effects in the Transmission of Saturated Molecules.

ABSTRACT: The single-molecule conductance of saturated molecules can potentially be fully suppressed by destructive quantum interference in their σ-system. However, only few molecules with σ-interference have been identified, and the structure-property relationship remains to be elucidated. Here, we explore the role of substituents in modulating the electronic transmission of saturated molecules. In functionalized bicyclo[2.2.2]octanes, the transmission is suppressed by σ-interference when fluorine substituents are applied. For bicyclo[2.2.2]octasilane and -octagermanes, the transmission is suppressed when carbon-based substituents are used, and such molecules are likely to be highly insulating. For the carbon-based substituents, we find a strong correlation between the appropriate Hammett constants and the transmission. The substituent effect enables systematic optimization of the insulating properties of saturated molecular cores.

SUBMITTER: Garner MH

PROVIDER: S-EPMC9955259 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Substituent Control of σ-Interference Effects in the Transmission of Saturated Molecules.

Garner Marc H MH Koerstz Mads M Jensen Jan H JH Solomon Gemma C GC

ACS physical chemistry Au 20220414 4

The single-molecule conductance of saturated molecules can potentially be fully suppressed by destructive quantum interference in their σ-system. However, only few molecules with σ-interference have been identified, and the structure-property relationship remains to be elucidated. Here, we explore the role of substituents in modulating the electronic transmission of saturated molecules. In functionalized bicyclo[2.2.2]octanes, the transmission is suppressed by σ-interference when fluorine substi ...[more]

PMID: 36855417

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