Rotational Magnetic Moments of the Alkali Molecules

Abstract

The rotational magnetic moments of the diatomic alkalis have been measured by the molecular-beam magnetic-resonance method. The values obtained for the gyromagnetic ratios ${g}_{J}$ (in nm) are: ${\mathrm{Li}}_{2}$, 0.10797; ${\mathrm{Na}}_{2}$, 0.03892; ${\mathrm{K}}_{2}$, 0.02162; ${\mathrm{Rb}}_{2}$, 0.00953; ${\mathrm{Cs}}_{2}$, 0.00547. The effect of the electric quadrupole interaction on the resonance is investigated, and found to lead to a slight broadening, but, in the limit of high $J$, to no displacement. An interpretation of the results in terms of the irrotational-flow model used by Espe for hydrogen is given.