Theory of Indirect Nuclear-Spin Interactions in Lead

The Ruderman-Kittel ($A_{12}$) and pseudodipolar coupling constants ($B_{12}$) in lead have been calculated relativistically using a procedure developed earlier and adapted to Dirac orthogonalized-plane-wave functions. For the conduction electrons, pseudo wave functions were obtained from the pseudopotential parameters of Anderson and Gold, the plane waves in the linear combination being replaced by Dirac orthogonalized-plane-wave functions. Our theoretical values for $A_{12}$ and $B_{12}$ are 4811 and 1477 cps, respectively, in reasonable agreement with experimental values of 4800±500 and 2200±200 cps.