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Quantum interference effects at room temperature in OPV-based single-molecule junctions.

ABSTRACT: Interference effects on charge transport through an individual molecule can lead to a notable modulation and suppression on its conductance. In this letter, we report the observation of quantum interference effects occurring at room temperature in single-molecule junctions based on oligo(3)-phenylenevinylene (OPV3) derivatives, in which the central benzene ring is coupled to either para- or meta-positions. Using the break-junction technique, we find that the conductance for a single meta-OPV3 molecule wired between gold electrodes is one order of magnitude smaller than that of a para-OPV3 molecule. Theoretical calculations confirm the occurrence of constructive and destructive interference in the para- and meta-OPV3 molecules respectively, which arises from the phase difference of the transmission coefficients through the molecular orbitals.

SUBMITTER: Arroyo CR

PROVIDER: S-EPMC3663707 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Quantum interference effects at room temperature in OPV-based single-molecule junctions.

Arroyo Carlos R CR Frisenda Riccardo R Moth-Poulsen Kasper K Seldenthuis Johannes S JS Bjørnholm Thomas T van der Zant Herre Sj HS

Nanoscale research letters 20130516 1

Interference effects on charge transport through an individual molecule can lead to a notable modulation and suppression on its conductance. In this letter, we report the observation of quantum interference effects occurring at room temperature in single-molecule junctions based on oligo(3)-phenylenevinylene (OPV3) derivatives, in which the central benzene ring is coupled to either para- or meta-positions. Using the break-junction technique, we find that the conductance for a single meta-OPV3 mo ...[more]

PMID: 23679986

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