Magnetism in 1D Cobalt-Cyclopentadienyl Sandwich Molecular Wire

A challenge for technological applications at the nanometer scale is to find magnetic materials with reduced dimensionality. Recent theoretical studies have predicted ferromagnetic and half-metallic behavior for the 1D-organometallic benzen vanadium wire. Here we discuss a variety of magnetic orderings such as anti-ferromagnetic and ferrimagnetic half-metallicity in the cobaltocen Co2(C5H5)2 nanowire. We performed DFT-calculations to optimize its geometry and used the NMTO downfolding technique to construct the real-space low energy Hamiltonian. To describe electronic correlations beyond the mean-field, we used the developed Variational Cluster Approach. Our preliminary results show that non-quasiparticle states appear in the half-metallic gap, which reduce considerably the spin polarization of such a wire. Ab-initio electron transport calculations are in progress to establish the role of cobaltocen nanowire as part of a future spin filter.