Ab initio investigation on electronic properties of the adenine molecule contacted with gold electrodes: effects of an external electric field

作者：Moghaddam H M^*; Jelodar M D

来源：Indian Journal of Physics and Proceedings of the Indian Association for the Cultivation of Science, 2013, 87(2): 99-105.

DOI：10.1007/s12648-012-0204-1

• Molecular wire
• Adenine
• Density Functional Theory

A theoretical investigation using density functional theory is performed on the electronic properties of a model molecular wire under an external electric field (EF), such as electronic structure and geometry. The molecular wire is modeled as 4Au/S-Adenine-S/4Au where Adenine is a base of deoxyribonucleic acid molecule acting as a molecular bridge. According to our results the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) decreases with exerting low EF. The application of EF may increase the molecular conjugation and the induced dipole moment. Moreover, the spatial distribution of frontier molecular orbitals moves from a fully delocalized form over whole molecular wire to a partially localized in terminal side which is dependent to EF strength. Accumulated natural bond orbital (NBO) charge on Au, S and NH2 group show that there is a close relationship among these factors and HOMO-LUMO gap. We would also expect an ohmic behavior of the current through the model wire.

• 出版日期2013-2