MAGNETIC-DIPOLE HYPERFINE-STRUCTURE CONSTANTS FOR THE ND2 TRIPLET-STATES OF SC-II AND Y-II

We report magnetic-dipole hyperfine-structure constants for Sc II 3d2 3P(1,2) and Y II 4d2 3P(1,2), 1D(2), which unlike the Dirac-Fock results are in excellent agreement with experiment. Theoretical values are (-108.87, -30.49, 47.01, 11.25, -22.98 MHz), compared with experiment (-107.3, -27.9, 46.56, 11.60, -26.40 MHz). We also predict that the hyperfine constant for Y II 4d2 3F2 is -149.94 MHz. Our calculations were done with nonrelativistic (Sc II) and relativistic (Y II) many-body theory. We found it unnecessary to include any off-diagonal hyperfine-coupling effects.