Relativistic calculation of magnetic linear response functions using the Korringa–Kohn–Rostoker Green's function method

The relativistic KKR (Korringa–Kohn–Rostoker) Green's function method of band-structure calculation supplies an extremely flexible basis for calculating magnetic linear response functions of solids. An important feature of this approach is that it accounts properly for the influence of all relativistic effects. A brief introduction to this formalism is presented, together with some recent extensions to it. In particular, the inclusion of the orbital magnetization density induced by an external magnetic field allows a direct comparison with experiment for many different properties. This is demonstrated for the induced magnetic form factor, the magnetic susceptibility and the Knight shift of transition metals. A further appealing feature of the KKR formalism is that it is applicable in principle to any complex system. This property is exemplified by applications for the disordered alloy systems Ag x Pd 1− x and Ag x Pt 1− x that are treated with the help of the coherent potential approximation alloy theory.