Theoretical Study of Donor--Bridge-Acceptor Unimolecular Electric Rectifier
详细信息 查看全文
- 作者：Aleksandar Staykov ; Daijiro Nozaki ; Kazunari Yoshizawa
- 刊名：Journal of Physical Chemistry C
- 出版年：2007
- 出版时间：August 9, 2007
- 年：2007
- 卷：111
- 期：31
- 页码：11699 - 11705
- 全文大小：464K
- 年卷期：v.111,no.31(August 9, 2007)
- ISSN：1932-7455
文摘
The electrical rectifying properties of a single-molecule nanowire from the type donor-
-bridge-acceptorare investigated by means of the nonequilibrium Green's function method, combined with density functionaltheory (NEGF-DFT). The investigated nanowire is an oligo-1,4-phenylene ethylene with -donor and-acceptor groups attached on opposite sides of the molecule. The donor and acceptor wires are separated bya -bridge, in contrast to the Aviram-Ratner rectifier, which is a donor-
-bridge-acceptor diode. A modelmore similar to the real molecular electronic device is considered with relaxation of the molecular geometry,under the interaction with external electric field, taking into account its influence on the electronic propertiesof the nanowire. An asymmetric current-bias (I-V) diagram is observed, with a conductance ratio of 7. Theanalysis of the spatial distribution of frontier orbitals, the highest occupied molecular orbital-lowest unoccupiedmolecular orbital ( HOMO-LUMO) gaps, and the transmission spectra give an inside view of the observedresults.
-bridge-acceptorare investigated by means of the nonequilibrium Green's function method, combined with density functionaltheory (NEGF-DFT). The investigated nanowire is an oligo-1,4-phenylene ethylene with -donor and-acceptor groups attached on opposite sides of the molecule. The donor and acceptor wires are separated bya -bridge, in contrast to the Aviram-Ratner rectifier, which is a donor--bridge-acceptor diode. A modelmore similar to the real molecular electronic device is considered with relaxation of the molecular geometry,under the interaction with external electric field, taking into account its influence on the electronic propertiesof the nanowire. An asymmetric current-bias (I-V) diagram is observed, with a conductance ratio of 7. Theanalysis of the spatial distribution of frontier orbitals, the highest occupied molecular orbital-lowest unoccupiedmolecular orbital ( HOMO-LUMO) gaps, and the transmission spectra give an inside view of the observedresults.