Non-collinear magnetic structures in bulk magnets and nanomaterials are subjects of intensive current research. These investigations are triggered by promising potential applications in magnetic recording and logics devices, as well as in spintronics. Particularly highlighted objects of research are topologically protected magnetic skyrmions or chiral magnetic domain walls. Controlling the motion of these magnetic patterns is essential for the mentioned applications. 

In this PhD work we combine ab initio and spin-model simulations to study the formation and dynamics of complex magnetic structures.  In calculating the magnetic interactions, we use well-established tools like the relativistic torque method or the spin-cluster expansion, but we also try to employ the spin-spiral method that provides a proper account of induced magnetic moments. The relativistic extension of this method within the multiple scattering Green's function technique displays an ambitious part of the work. Particular emphasis will be paid to the manipulation of the Dzyaloshinskii-Moriya interactions at interfaces and to account for electron correlation effects via the LDA+U method.  The magnetic ground state and the finite temperature behavior of the systems will be studied by using Monte Carlo and/or atomistic spin-dynamics simulations. We plan systematic investigations of systems which are presently at the core of experimental interest, like Co/Ni(Pt) or Fe/Ir multilayers.