Modulation of destructive quantum interference by bridge groups in truxene-based single-molecule junctions

We have used scanning tunneling microscopy to create and study single molecule junctions with thioether-terminated oligothiophene molecules. We find that the conductance of these junctions increases upon formation of charge transfer complexes of the molecules with tetracyanoethene, and that the extent of the conductance increase is greater the longer is the oligothiophene, i.e. the lower is the conductance of the uncomplexed molecule in the junction. We use non-equilibrium Green's function transport calculations to explore the reasons for this theoretically, and find that new resonances appear in the transmission function, pinned close to the Fermi energy of the contacts, as a consequence of the charge transfer interaction. This is an example of a room temperature quantum interference effect, which in this case boosts junction conductance in contrast to earlier observations of QI that result in diminished conductance.

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Fermi energy dependence of first- and second-order Raman spectra in graphene: Kohn anomaly and quantum interference effect

Physical Review B ◽

10.1103/physrevb.94.075104 ◽

2016 ◽

Vol 94 (7) ◽

Cited By ~ 12

Author(s):

Eddwi H. Hasdeo ◽

Ahmad R. T. Nugraha ◽

Mildred S. Dresselhaus ◽

Riichiro Saito

Keyword(s):

Raman Spectra ◽

Energy Dependence ◽

Fermi Energy ◽

Interference Effect ◽

Quantum Interference ◽

Second Order ◽

Quantum Interference Effect

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Quantum interference effect of single-molecule conductance influenced by insertion of different alkyl length

Electrochemistry Communications ◽

10.1016/j.elecom.2016.05.002 ◽

2016 ◽

Vol 68 ◽

pp. 86-89 ◽

Cited By ~ 10

Author(s):

Ze-Wen Hong ◽

Mohamed Ali Ben Aissa ◽

Lin-Lu Peng ◽

Hujun Xie ◽

De-Li Chen ◽

...

Keyword(s):

Single Molecule ◽

Interference Effect ◽

Quantum Interference ◽

Quantum Interference Effect ◽

Alkyl Length

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Single-Molecule Phenyl-Acetylene-Macrocycle-Based Optoelectronic Switch Functioning as a Quantum-Interference-Effect Transistor

Physical Review Letters ◽

10.1103/physrevlett.109.186801 ◽

2012 ◽

Vol 109 (18) ◽

Cited By ~ 27

Author(s):

Liang-Yan Hsu ◽

Herschel Rabitz

Keyword(s):

Single Molecule ◽

Interference Effect ◽

Quantum Interference ◽

Phenyl Acetylene ◽

Quantum Interference Effect ◽

Effect Transistor ◽

Optoelectronic Switch

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Quantum interference effect in the charge transport through single-molecule benzene dithiol junction at room temperature: An experimental investigation

Chinese Chemical Letters ◽

10.1016/j.cclet.2017.06.015 ◽

2018 ◽

Vol 29 (1) ◽

pp. 147-150 ◽

Cited By ~ 7

Author(s):

Guogang Yang ◽

Hao Wu ◽

Junying Wei ◽

Jueting Zheng ◽

Zhaobin Chen ◽

...

Keyword(s):

Experimental Investigation ◽

Charge Transport ◽

Single Molecule ◽

Interference Effect ◽

Quantum Interference ◽

Room Temperature ◽

Quantum Interference Effect

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Charge Transfer Complexation Boosts Molecular Conductance Through Fermi Level Pinning

10.26434/chemrxiv.7110788.v1 ◽

2018 ◽

Author(s):

Kun Wang ◽

Andrea Vezzoli ◽

Iain Grace ◽

Maeve McLaughlin ◽

Richard Nichols ◽

...

Keyword(s):

Charge Transfer ◽

Single Molecule ◽

Quantum Interference ◽

Transmission Function ◽

Scanning Tunneling ◽

Charge Transfer Complexes ◽

Tunneling Microscopy ◽

Quantum Interference Effect ◽

Single Molecule Junctions ◽

Charge Transfer Complexation

We have used scanning tunneling microscopy to create and study single molecule junctions with thioether-terminated oligothiophene molecules. We find that the conductance of these junctions increases upon formation of charge transfer complexes of the molecules with tetracyanoethene, and that the extent of the conductance increase is greater the longer is the oligothiophene, i.e. the lower is the conductance of the uncomplexed molecule in the junction. We use non-equilibrium Green's function transport calculations to explore the reasons for this theoretically, and find that new resonances appear in the transmission function, pinned close to the Fermi energy of the contacts, as a consequence of the charge transfer interaction. This is an example of a room temperature quantum interference effect, which in this case boosts junction conductance in contrast to earlier observations of QI that result in diminished conductance.

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Mechanically-Tunable Quantum Interference in Ferrocene-Based Single-Molecule Junctions

10.26434/chemrxiv.12252059 ◽

2020 ◽

Author(s):

María Camarasa-Gómez ◽

Daniel Hernangómez-Pérez ◽

Michael S. Inkpen ◽

Giacomo Lovat ◽

E-Dean Fung ◽

...

Keyword(s):

Single Molecule ◽

Quantum Interference ◽

Degrees Of Freedom ◽

Building Blocks ◽

Ferrocene Derivative ◽

Single Molecule Junctions ◽

Molecule Junction ◽

Single Molecule Junction ◽

The Impact ◽

D Orbitals

Ferrocenes are ubiquitous organometallic building blocks that comprise a Fe atom sandwiched between two cyclopentadienyl (Cp) rings that rotate freely at room temperature. Of widespread interest in fundamental studies and real-world applications, they have also attracted some interest as functional elements of molecular-scale devices. Here we investigate the impact of the configurational degrees of freedom of a ferrocene derivative on its single-molecule junction conductance. Measurements indicate that the conductance of the ferrocene derivative, which is suppressed by two orders of magnitude as compared to a fully conjugated analog, can be modulated by altering the junction configuration. Ab initio transport calculations show that the low conductance is a consequence of destructive quantum interference effects that arise from the hybridization of metal-based d-orbitals and the ligand-based π-system. By rotating the Cp rings, the hybridization, and thus the quantum interference, can be mechanically controlled, resulting in a conductance modulation that is seen experimentally.

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