Marwa abdulhussaien kadhim 1, Oday A. Al-Owaedi 2
1,2 Dept. of Laser Physics, College of Science ,University of Babylon / Babylon /Iraq;


: In this study, Quantum interference (QI) is one of the most fundamentals science, which can be a powerful strategy to control and enhance the electric, thermoelectric and spectral properties of single molecules. Here, the density-functional-theory-based quantum transport calculations have been used to figure out the electrical conductance (G/G0), which supplies unique understanding into the thermopower (S) and emission oscillator strength (fem) of from a series of oligophenylene-ethynylene (OPE) derivatives with thiol end-groups, and para or meta transport connections, which underpins their spectral and heat transport properties. The molecules with meta connection (OPE-4,5,6) demonstrated the signature of a destructive quantum interference, which resulted to a low conductance (0.65×10-4, 0.5×10-6, and 0.17×10-6) respectively produce a high thermopower (165, 182, and 266 μVK-1). These structures yield very low emission oscillator strength (0.96, 0.75, and 0.66) respectively. In contrast, the para linking in molecules OPE-1,2,3 led to a constructive quantum interference, which was the reason for the high conductance (0.52×10-3, 0.88×10-3, and 0.22×10-2) respectively. These molecule exhibited a low thermopower (22, 21, and 13), and a high emission oscillator strength (2.15, 2.15, and 2.03) respectively. Finally, the properties of all molecules studied here are dominated by the highest occupied molecular orbital (HOMO) level.


:: Quantum, Nano-electronic , Gaussian, GOLLUM, SIESTA.

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