Effects of basis set contraction on relativistic and Breit interaction energies

Abstract

Relativistic self-consistent field (SCF) calculations have been performed on a number of neutral and ionized atoms with basis sets of contracted and uncontracted Gaussian-type functions. Both Dirac-Fock and Dirac-Fock-Breit SCF calculations have been performed with the intent of observing to what extent basis set contraction affects the calculated relativistic and Breit interaction contributions to total atomic energy. It is found that extensive basis set contraction has relatively little effect on the calculated relativistic and Breit interaction energies.