EN
In this paper we present partial densities of states for spin-polarized antiferromagnetic phase of Zn_{0.5}Co_{0.5}Se as well as schematic layouts of the bands, obtained using the ab initio self-consistent semi-relativistic linear muffin tin orbital method. We also present, from theoretical point of view, the analysis of influence of the transition metal cobalt on the electronic structure of a pure ZnSe.