Probing the effect of electric field in 9,10-dimethoxy-2,6-bis(2-p-tolylethynyl)anthracene molecular nanowire using quantum chemical and charge density analysis

Abstract

The effect of electric field (EF) in a newly designed molecular nanowire 9,10-dimethoxy-2,6-bis(2-p-tolylethynyl)anthracene has been analysed theoretically from the structural and electronic charge transport properties using quantum chemical and charge density calculations. The applied EF (0–0.36 VÅ− 1) alters the molecular conformation, charge density distribution, electrostatic properties and the electronic energy levels of the molecule. Furthermore, the applied EF decreases the highest occupied molecular orbital–lowest unoccupied molecular orbital gap significantly from 1.775 to 0.258 eV and it also induces polarisation in the molecule, which leads to increase the dipole moment of the molecule. The electrostatic potential for various levels of applied EF reveals the charge-accumulated regions of the molecule. The I–V characteristics of the molecule have been studied against various applied fields using Landauer formalism.