TIME-REVERSAL SYMMETRY AND 2-PARTICLE FERMION MANY-BODY-OPERATORS IN FN

Time reversal selection rules (TRSRs) are given for atomic electron op erators in the Racah group chain, in particular, for orthogonal time-e ven/odd many-body operators at the Sp4l+2 and SU2S x SO3L levels. The complementary effects of TRSRs at different levels in a group chain an d the consistency of TRSRs within a product group are discussed. Appli cations of these TRSRs are made to correlation crystal field theory, T rees operator contributions from second-order Coulomb interaction, and certain time-even two-body scalar operators used in evaluating the en ergy structure of many-electron systems.