Abstract
To study the electronic transport of molecular wire circuits, we present a time-independent scattering formalism which includes an ab initio description of the molecular electronic structure. This allows us to obtain the molecule-metal coupling description at the same level of theory. The conductance of junction α, α′ xylyl dithiol and benzene- 1,4-dithiol between gold electrodes is obtained and compared with available experimental data. The conductance depends dramatically on the relative position of the Fermi energy of the metal with respect to the molecular levels. We obtain an estimate for the injecting energy of the electron onto the molecule by varying the distance between the molecule and the attached gold clusters. Contrary to the standard assumption, we find that the injecting energy lies close to the molecular highest occupied molecular orbital, rather than in the middle of the gap; it is just the work function of the bulk metal. Finally, the adequacy of the widely used extended Hückel method for conductance calculations is discussed.
| Original language | English |
|---|---|
| Pages (from-to) | 6997-7002 |
| Number of pages | 6 |
| Journal | Journal of Chemical Physics |
| Volume | 111 |
| Issue number | 15 |
| Publication status | Published - Oct 15 1999 |
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ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
Cite this
The injecting energy at molecule/metal interfaces : Implications for conductance of molecular junctions from an ab initio molecular description. / Yaliraki, S. N.; Roitberg, A. E.; Gonzalez, C.; Mujica, Vladimiro; Ratner, Mark A.
In: Journal of Chemical Physics, Vol. 111, No. 15, 15.10.1999, p. 6997-7002.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The injecting energy at molecule/metal interfaces
T2 - Implications for conductance of molecular junctions from an ab initio molecular description
AU - Yaliraki, S. N.
AU - Roitberg, A. E.
AU - Gonzalez, C.
AU - Mujica, Vladimiro
AU - Ratner, Mark A
PY - 1999/10/15
Y1 - 1999/10/15
N2 - To study the electronic transport of molecular wire circuits, we present a time-independent scattering formalism which includes an ab initio description of the molecular electronic structure. This allows us to obtain the molecule-metal coupling description at the same level of theory. The conductance of junction α, α′ xylyl dithiol and benzene- 1,4-dithiol between gold electrodes is obtained and compared with available experimental data. The conductance depends dramatically on the relative position of the Fermi energy of the metal with respect to the molecular levels. We obtain an estimate for the injecting energy of the electron onto the molecule by varying the distance between the molecule and the attached gold clusters. Contrary to the standard assumption, we find that the injecting energy lies close to the molecular highest occupied molecular orbital, rather than in the middle of the gap; it is just the work function of the bulk metal. Finally, the adequacy of the widely used extended Hückel method for conductance calculations is discussed.
AB - To study the electronic transport of molecular wire circuits, we present a time-independent scattering formalism which includes an ab initio description of the molecular electronic structure. This allows us to obtain the molecule-metal coupling description at the same level of theory. The conductance of junction α, α′ xylyl dithiol and benzene- 1,4-dithiol between gold electrodes is obtained and compared with available experimental data. The conductance depends dramatically on the relative position of the Fermi energy of the metal with respect to the molecular levels. We obtain an estimate for the injecting energy of the electron onto the molecule by varying the distance between the molecule and the attached gold clusters. Contrary to the standard assumption, we find that the injecting energy lies close to the molecular highest occupied molecular orbital, rather than in the middle of the gap; it is just the work function of the bulk metal. Finally, the adequacy of the widely used extended Hückel method for conductance calculations is discussed.
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M3 - Article
VL - 111
SP - 6997
EP - 7002
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
SN - 0021-9606
IS - 15
ER -