Calculation of nuclear magnetic resonance shieldings and magnetic susceptibilities using multiconfiguration Hartree–Fock wave functions and local gauge origins

A multiconfiguration generalization of the individual gauge for localized orbitals (IGLO) method for the calculation of magnetic properties such as susceptibilities and nuclear magnetic resonance chemical shifts is presented in detail. This includes a rederivation of the IGLO method by means of a nonlocal gauge transformation. The method is most successfully applied if strong (static) correlation effects have to be taken into account.