Branching ratios of Hg5dand Cd4d: Dirac-Fock calculations

Dirac-Fock (DF) and Dirac-Slater (DS) calculations of the photoionization of Hg $5d$ and Cd $4d$ have been performed in an effort to assess the utility of such calculations for the prediction of subshell cross sections and branching ratios as well as to attempt to elucidate the effects of relativistic (especially spin-orbit) interactions. Our results indicate that in both cases, the subshell cross section is predicted rather well by the DF results, while the DS is too large (by a factor of ∼2) and peaks too close to threshold. For the Hg $5d$ branching ratio, the DF values are in excellent agreement with experiment and the DS results are in pretty fair agreement as well. For Cd $4d$, on the other hand, neither calculation is entirely satisfactory; away from threshold the DF result, however, is reasonably good. The possible origin and implications of these results are discussed.