Ab initio correlation effects on the electronic and transport properties of metal(II)-phthalocyanine based devices

摘要

Using first principles calculations in the framework of Density FunctionalTheory, we investigated the electronic and transport properties ofmetal(II)-phthalocyanine (M(II)Pc) systems, both in a single moleculeconfiguration and in a model-device geometry. In particular, using theCopper(II)- and Manganese(II)-Pc as prototypical examples, we studied howelectronic correlations on the central metal-ion influence the analysis of theelectronic structure of the system and we demonstrated that the choice of theexchange-correlation functional, also beyond the standard local or gradientcorrected level, is of crucial importance for a correct interpretation of thedata. Finally, our electronic transport simulations have shown thatM(II)Pc-based devices can act selectively as molecular conductors, as in thecase of Copper, or as spin valves, as in the case of Manganese, demonstratingonce more the great potential of these systems for molecular nanoelectronicsapplications.