Broadly speaking, NSCD can be seen as a localized version of classical magnetic circular dichroism (MCD). In MCD the sample exhibits different coefficients of molar absorption for the LCP and RCP components of light when it is placed in a magnetic field with a component parallel to the path of the propagation of the beam. In NSCD, the magnetic field perturbation is not introduced from the outside, but from within the molecule by the individual nuclear magnetic moments. In analogy to MCD, NSCD is then observed when the average magnetization of the sample from the nuclear magnetic moments is at least partially aligned with the direction of the light beam. Since NSCD arises from differential absorption coefficients for RCP and LCP, a proper characterization of the excited states is important for its faithful description. In addition, since it also involves interactions with the nuclear magnetic moments via a hyperfine interaction operator ( ĥhf ), capturing the electronic properties near the nucleus is also essential.