  We present a theoretical study of the spin transport properties of
mono-atomic magnetic chains with a focus on the spectroscopical features of the
I-V curve associated to spin-flip processes. Our calculations are based on the
s-d model for magnetism with the electron transport treated at the level of the
non-equilibrium Green's function formalism. Inelastic spin-flip scattering
processes are introduced perturbatively via the first Born approximation and an
expression for the associated self-energy is derived. The computational method
is then applied to describe the I-V characteristics and its derivatives of one
dimensional chains of Mn atoms and the results are then compared to available
experimental data. We find a qualitative and quantitative agreement between the
calculated and the experimental conductance spectra. Significantly we are able
to describe the relative intensities of the spin excitation features in the I-V
curve, by means of a careful analysis of the spin transition selection rules
associated to the atomic chains.
