Magnetically Induced Current Density from Numerical Positional Derivatives of Nucleus Independent Chemical Shifts

Abstract

Instead of computing magneticallly induced (MI) current densities (CD) via the wave function and their quatum mechanical definition one can also use the differential form of the Amp\`ere-Maxwell law to obtain them from spatial derivatives of the induced magnetic field. In magnetic molecular response calculations, the latter can be done by numerical derivativation of the so called ``nucleus-independent chemical shifts'' (NICS) which are avaialable to many standard quantum chemical programs. The resulting numerical MICD data is in contrast to other numerically obtained MICDs computed via the wave function route, virtually divergence-free.