Relativistic calculation of hyperfine and electron spin resonance parameters in diatomic molecules

The four-component formulation of the Dirac–Hartree–Fock (DHF) approximation is used to calculate the electronic g-tensors and nuclear hyperfine interaction A-tensors for a number of open-shell diatomic species. The four-component approach makes it possible to include all relativistic single-particle effects involving the calculated magnetic interactions within the spinor structure, using a compact computational formulation. Results for most of the molecules investigated here are in good agreement with experiment.