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Updated: May 10, 2026
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Transport properties of binuclear metal complexes of the VIII group using a simplified NEGF-DFT approach
Vincenzo Barone1, Ivo Cacelli, Alessandro Ferretti
1Scuola Normale Superiore, Piazza dei Cavalieri, I-56126 Pisa, Italy. vincenzo.barone@sns.it
Abstract:
We report on a theoretical study of the electronic transport properties of binuclear complexes of metals of the VIII group bridged by pyrazine. Metal-porphyrazine units have been combined in order to investigate symmetric and non-symmetric species with particular focus on their current rectification properties. Transmission functions and I-V characteristics of the various species have been computed using a Non-Equilibrium Green Function with a simplified treatment of the molecule-lead interaction. The results obtained show an overall moderate asymmetry in the current along the molecules, which is of the donor-σ-acceptor type and follow the trend of the ionization potential of the metals in the binuclear system. The bias-dependent rectification ratio, which is significant in a limited voltage window, can be explained in terms of the alignment of the occupied orbitals of the metallic fragments that contribute to the HOMO and HOMO - 1 of the supermolecule. The possible improvement of the rectification performance of such a class of molecules has also been investigated exploiting suitable substitution by electron-withdrawing groups.
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