Relativistic electron densities and isomer shifts in transition-metal ions

Relative isomer shifts of $3d$, $4d$, and $5d$ ions are obtained by calculation of atomic electron charge densities, using numerical Hartree-Fock and multiconfiguration Dirac-Fock theory, with exact exchange, to describe the ionic systems. The relativistic calculations, for both point and finite nucleus models, are compared with results obtained from the nonrelativistic calculations augmented by one-electron relativistic corrections. The relativistic charge densities and experimental isomer shifts are employed to deduce estimates of changes in mean square nuclear radii.