Relativistic effects on molecular hyperfine interactions: Application to XeF and CsO

Abstract
A relativistic theory of molecular hyperfine interactions is presented, based on the use of multiple scattering theory to generate approximate solutions to the Dirac equation. This approach should be especially useful for radicals with significant orbital contributions to the hyperfine tensor. Results for XeF and CsO are in good agreement with experiment, and show that orbital interactions are important for both heavy and light atoms, and that A⊥ for fluorine in XeF is likely to be negative.