The Magnetic Moment of theK39Nucleus

Starting with the ${\mathrm{K}}^{+}$ field given by Hartree, a $4s$ wave function has been found by numerical integration. The orthogonality correction diminishes the value of the wave function at the origin by about one-third. The experimental value of the hyperfine structure separation of the ${}_{}{}^2{}_{}{}^{}S$ normal state is 0.015 ${\mathrm{cm}}^{-1\mathrm{}}$. From this is calculated a molecular magnetic moment of 1.2 nuclear magnetons, as compared with the value of 0.38 nuclear magnetons calculated by Millman, Fox and Rabi on the basis of the modified Goudsmit's formula. The disagreement seems to be due chiefly to the possibility that the single electron wave functions of Fermi and Segré are not mutually orthogonal.