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.