Quasirelativistic Hartree-Fock equations consistent with Breit-Pauli approach

The properties of the quasirelativistic Hartree-Fock equations are investigated. Different ways of forming the equations are discussed. The relativistic corrections employed in the traditional quasirelativistic Hartree-Fock equations are compared with the ones used within the Breit-Pauli approach. The two-electron contact interactions are revised and the new versions of the quasirelativistic Hartree-Fock equations are considered. The solutions of these equations are compared among themselves and also with those obtained within the Dirac-Fock and nonrelativistic Hartree-Fock approaches. Solution data are provided for some heliumlike, neonlike, and mercurylike ions