Nonexponential Length Dependence of Molecular Conductance in Acene-Based Molecular Wires
| Autor: | Paulina Rocha, Anastazia Polakovsky, Jesús Valdiviezo, Julio L. Palma |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Bioengineering 02 engineering and technology 01 natural sciences Molecular physics symbols.namesake chemistry.chemical_compound Molecular wire Molecular conductance Nanotechnology Molecular orbital Instrumentation HOMO/LUMO Acene Electrodes Fluid Flow and Transfer Processes Process Chemistry and Technology 010401 analytical chemistry Fermi level Conductance Molecular scale electronics 021001 nanoscience & nanotechnology 0104 chemical sciences chemistry Semiconductors symbols Gold 0210 nano-technology |
| Zdroj: | ACS sensors. 6(2) |
| ISSN: | 2379-3694 |
| Popis: | In the nonresonant regime, molecular conductance decays exponentially with distance, limiting the fabrication of efficient molecular semiconductors at the nanoscale. In this work, we calculate the conductance of a series of acene derivatives connected to gold electrodes using density functional theory (DFT) combined with the nonequilibrium Green's function (NEGF) formalism. We show that these systems have near length-independent conductance and can exhibit a conductance increase with molecular length depending on the connection to the electrodes. The analysis of the molecular orbital energies and transmission functions attribute this behavior to the dramatic decrease of the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap with length, which shifts the transmission peaks near the Fermi level. These results demonstrate that the anchoring configuration determines the conductance behavior of acene derivatives, which are optimal building blocks to fabricate single-molecule devices with tunable charge transport properties. |
| Databáze: | OpenAIRE |
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