Reduced matrix elements of spin–spin interactions for the atomic ff-electron configurations

A re-examination of some major references on the intra-atomic magnetic interactions over the last six decades reveals that there exist some gaps or puzzles concerning the previous studies of the spin–spin interactions for the atomic ff-shell electrons. Hence, tables are provided for the relevant reduced matrix elements of the four double-tensor operators zrzr (r=1,2,3r=1,2,3, and 4) of rank 2 in both the orbital and spin spaces. The range of the tables covers all states of the configurations from f4f4 to f7f7.