Spin filtering in molecular junction: magnetoresistance evaluation from wave-function calculations

The conductance of magnetic molecules opens new ways to probe the electronic structure of correlated systems. Based on a 2-electron/2-molecular orbital prototype system, the current-potential characteristics is inspected as a function of the differential magnetization of the electrodes sandwiching the molecule within a multideterminantal framework. The bias-dependent magnetoresistance effect along the junction reflects the nature and energetics of the different multiplets, obtained within the multiconfigurational wave-function approach. From the wave-function description, a modulation of the magnetoresistance ratio is anticipated and both direct and inverse regimes are observed depending on the electronic structure of the junction.