Spin-Orbit Contribution to the Zero-Field Splitting of the Oxygen Molecule

Abstract
The spin‐orbit contribution to the zero‐field splitting of the oxygen molecule is calculated using the complete spin‐orbit Hamiltonian. All calculations are performed at the equilibrium internuclear distance R=2.282 a.u. The spin‐orbit contribution to D is found to be 0.3125 cm−1 which is about 7% of the total D value.