The Nuclear Moments ofSe79

Microwave measurements of the $J=2\mathrm{}\to 3$ rotational transition of OCSe containing the radioactive-nucleus ${\mathrm{Se}}^{79}$ have established the ${\mathrm{Se}}^{79}$ spin as $\frac{7}{2}$ and the ${\mathrm{Se}}^{79}$ quadrupole moment as 0.7×${10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$±20 percent. The quadrupole coupling constant $\mathrm{eqQ}$ is 752.09±0.05 Mc/sec. The magnetic moment of ${\mathrm{Se}}^{79}$ has been determined as -1.015±0.015 nuclear magnetons by observation of the Zeeman splitting of one hyperfine component. The $\frac{7}{2}$ spin and the large positive $Q$ are inconsistent with the single-particle nuclear-shell model, but suggest the configuration ${{\left(g_{\frac{9}{2}}\right)}^2}_{\frac{7}{2}}$. This assignment is substantiated by the negative magnetic moment.