Magnetic-dipole hyperfine-structure constants for thend2triplet states of Sc ii and Y ii

We report magnetic-dipole hyperfine-structure constants for Sci i 3${\mathit{d}}^{23}$ ${\mathit{P}}_{\mathrm{}(1,2)\mathrm{}}$ and Y i i 4${\mathit{d}}^{23}$ ${\mathit{P}}_{\mathrm{}(1,2)\mathrm{}}$ ${}_{}{}^1{}_{}{}^{}$ ${\mathit{D}}_{\mathrm{}\left(2\right)\mathrm{}}$, 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 i i4${\mathit{d}}^{23}$ ${\mathit{F}}_2$ is -149.94 MHz. Our calculations were done with nonrelativistic (Sc i i) and relativistic (Y i i) many-body theory. We found it unnecessary to include any off-diagonal hyperfine-coupling effects.