Polarization corrections for shielding and antishielding configurations of the copper atom

The level-crossing technique has been used to measure the hyperfine structure constants of the Cu63 nucleus in the (3d)104pP322 state. To extract a value for the nuclear quadrupole moment, configuration interaction effects are allowed for by performing a least-squares fit to the energy levels. The value obtained is in serious disagreement with a value for Q inferred from the (3d)9(4s)2 configuration. The copper moment may therefore serve as a test for Sternheimer or other polarization corrections that must be invoked to explain the discrepancy.