Theoretical Investigation of Magnetic Properties of 3d and 4f Compounds

3d and 4f complexes are studied by quantum chemical methods to understand their magnetic behavior. For the theoretical description, methods are needed that can take the open shell character of the molecules, several electronic states and spin orbit coupling into account. In this work, ab initio calculations have been performed to understand the magnetic behavior of the transition metal and lanthanide based systems. The investigations were focused on 3d/4f systems with different ligand fields and geometries.