CALCULATION OF SPIN-ORBIT COUPLING CONSTANTS IN DIATOMIC MOLECULES FROM HARTREE-FOCK WAVE FUNCTIONS

Spin-orbit coupling constants are calculated from Hartree-Fock wave functions of diatomic molecules using the Dirac Hamiltonian. For first-row diatomic hydrides, agreement with experiment is good (∼5%) provided that two-electron integrals are considered. These two-electron integrals may be interpreted as providing a shielding of the nuclear charge; they reduce the computed value of the coupling constant from that found from simple Zr3 terms. The applications to II2 states of BeH, CH, and OH are specifically considered. © 1969 The American Physical Society.