ON THE INCLUSION OF THE BREIT INTERACTION TERM IN THE CLOSED-SHELL GENERATOR-COORDINATE DIRAC-FOCK FORMALISM

The generator coordinate Dirac-Fock formalism with the inclusion of th e frequency-independent Breit interaction term is presented. The integ ration of the Dirac-Fock equations is performed through an integral di scretization technique in order to preserve the continuous character o f the original generator coordinate formalism. The inclusion of the Br eit interaction term in the generator coordinate Dirac-Fock formalism is assessed through Dirac-Fock-Breit calculations for the relativistic closed-shell atoms with d and f orbitals, i.e., from zinc (Z=30) up t o nobelium (Z=102), by using a universal Gaussian basis set generated previously by employing the generator coordinate Dirac-Fock method. Th e Dirac-Fock-Breit energy results presented in this work are the best, so far, obtained for the relativistic closed-shell atoms from Zn (Z=3 0) through No (Z=102) by using Gaussian-type functions, and show the e fficacy of the generator coordinate Dirac-Fock method in performing ac curate Dirac-Fock-Breit calculations. (C) 1996 American Institute of P hysics.