ABSTRACT
Natural optical activity, which occurs exclusively in chiral media, and magnetic optical activity, which is induced by a longitudinal magnetic field, show a strong phenomenological resemblance. An electrical conductor for instance may be chiral because of several reasons. Interpreting magnetic optical activity as a sign of magnetically induced chirality, Pasteur was the first to search-in vain-for an enantioselective effect of magnetic fields. The true magnetochiral dichroism also generates an enantiomeric excess that is independent of the polarization state and intensity of the light, as long as the latter is high enough so that photoresolution is much faster than thermal racemization. Chirality is a very general symmetry concept, and its consequences are not limited to the optical properties of systems. The unpolarized incident light beam is described as an electromagnetic wave consisting of two circularly polarized components of equal amplitude, propagating in the z-direction.
