Abstract
Single-molecule junctions are the constitutive components of molecular electronics circuits. For any potential application, the energy gap in the junction, i.e., the accumulated energy difference between the electrode Fermi level and the two frontier energy levels of the molecule, is a key property. Here, using the nonequilibrium Green's function coupled to the density functional theory framework (NEGF-DFT) method, we show that the gap of the molecule inserted between electrodes can differ largely from the gap of the same molecule, at the isolated level. It can be widely compressed by tuning the alignment mechanism at each metal/molecule interface. In the context of molecular rectification, we show that this mechanism relates to the pinning effect. We discuss the different parameters affecting the compression of the gap and its efficiency. Interestingly, we find that the structure both of the molecule and of the anchoring group plays an important role. Finally, we investigate the evolution of these features out-of-equilibrium.
| Original language | English |
|---|---|
| Pages (from-to) | 3013-3024 |
| Number of pages | 12 |
| Journal | Journal of Physical Chemistry C |
| Volume | 121 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - Feb 9 2017 |
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Energy(all)
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
Cite this
Molecular Junctions : Control of the Energy Gap Achieved by a Pinning Effect. / Van Dyck, Colin; Ratner, Mark A.
In: Journal of Physical Chemistry C, Vol. 121, No. 5, 09.02.2017, p. 3013-3024.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Molecular Junctions
T2 - Control of the Energy Gap Achieved by a Pinning Effect
AU - Van Dyck, Colin
AU - Ratner, Mark A
PY - 2017/2/9
Y1 - 2017/2/9
N2 - Single-molecule junctions are the constitutive components of molecular electronics circuits. For any potential application, the energy gap in the junction, i.e., the accumulated energy difference between the electrode Fermi level and the two frontier energy levels of the molecule, is a key property. Here, using the nonequilibrium Green's function coupled to the density functional theory framework (NEGF-DFT) method, we show that the gap of the molecule inserted between electrodes can differ largely from the gap of the same molecule, at the isolated level. It can be widely compressed by tuning the alignment mechanism at each metal/molecule interface. In the context of molecular rectification, we show that this mechanism relates to the pinning effect. We discuss the different parameters affecting the compression of the gap and its efficiency. Interestingly, we find that the structure both of the molecule and of the anchoring group plays an important role. Finally, we investigate the evolution of these features out-of-equilibrium.
AB - Single-molecule junctions are the constitutive components of molecular electronics circuits. For any potential application, the energy gap in the junction, i.e., the accumulated energy difference between the electrode Fermi level and the two frontier energy levels of the molecule, is a key property. Here, using the nonequilibrium Green's function coupled to the density functional theory framework (NEGF-DFT) method, we show that the gap of the molecule inserted between electrodes can differ largely from the gap of the same molecule, at the isolated level. It can be widely compressed by tuning the alignment mechanism at each metal/molecule interface. In the context of molecular rectification, we show that this mechanism relates to the pinning effect. We discuss the different parameters affecting the compression of the gap and its efficiency. Interestingly, we find that the structure both of the molecule and of the anchoring group plays an important role. Finally, we investigate the evolution of these features out-of-equilibrium.
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U2 - 10.1021/acs.jpcc.6b07855
DO - 10.1021/acs.jpcc.6b07855
M3 - Article
VL - 121
SP - 3013
EP - 3024
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 5
ER -