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X. Zhao, R. Stadler:
"Density functional theory based electron transport study of coherent tunneling through cyclic molecules containing Ru and Os as redox active centers";
Physical Review B, 99 (2019), 115428.

In our theoretical study in which we combine a nonequilibrium Green's function approach with density functional theory we investigate branched compounds containing Ru or Os metal complexes in two branches, which due to their identical or different metal centers are symmetric or asymmetric. In these compounds the metal atoms are connected to pyridyl anchor groups via acetylenic and phenyl spacer groups in a metaconnection. We find there is no destructive quantum interference (DQI) feature in the transmission function near the Fermi level for the investigated molecules regardless of their symmetry, either in their neutral states or in their charged states. We map the structural characteristics of the range of molecules onto a simplified tight-binding model in order to identify the main differences between the molecules in this study and previously investigated ferrocene compounds in order to clarify the structural sources for DQI, which we found for the latter but not for the former. We also find that local charging on one of the branches changes only the conductance by about one order of magnitude, which we explain in terms of the spatial distributions and charge-induced energy shifts of the relevant molecular orbitals for the branched compounds.

Molecular electronics, quantum inferference, electron transport, density functional theory

http://dx.doi.org/10.1103/PhysRevB.99.115428

https://publik.tuwien.ac.at/files/publik_278865.pdf

Project Head Robert Stadler:
Elektrochemische Interferenz