Electronic transport on the two state “ON–OFF” of 1,3,3-trimethylindolino-6′-nitrobenzopyrylospiran as a light-driven molecular optical switch: A first-principle study

Abstract

Here, the electronic transport characteristics of the 1,3,3-trimethylindolino-6′-nitrobenzopyrylospiran were studied by using NEGF and DFT methods. By being exposed to UV or visible light, this molecule can change from its MC to SP states. The titled structure was optimized at B3LYP/6–311++G(d,p) level of theory. To obtain conductivity results, the electrons of metal and organic atoms were approached by the single-plus polarization (SZP) for single-zeta and double-plus polarization (DZP) for double zeta basis sets, respectively. We examined some factors in this study, including various molecule geometries, the type of surface materials (Platinum, gold, and silver), the switching ratio, the gap between HOMO and LUMO levels, and the transmission spectra, at different bias voltages. The outcomes show that conductivity transforms from an off-state (high resistance) to an on-state as the molecule switches from MC to SP form (low resistance).