Relativistic effects in the many electron atom

A review is given of the basic ideas as the starting point of relativistic calculations of atomic properties. Nonrelativistic limits are then discussed to exhibit the main differences between a relativistic and nonrelativistic treatment of atomic structure. The equivalent operator formalism is described and is applied to fine and hyperfine structures, the Zeeman effect, and transition probabilities. The problem of perturbation calculations in the relativistic scheme is briefly discussed and the calculation of relativistic radial wave functions is considered. (120 references) (U.S.)