Electric field gradients at rubidium sites in rubidium uranyl nitrate and quadrupole moments of ⁸⁵Rb and ⁸⁷Rb

The electronic structure along the axial direction of the uranyl ion in rubidium uranyl nitrate (RbUO2(NO3)(3)) has been probed by nuclear quadrupole resonance and nuclear magnetic resonance measurements of Rb-85 and Rb-87 quadrupole couplings. The parameter of interest in these experiments is the electric field gradient at the Rb sites, which may be compared with values computed by various theoretical approaches. From this analysis a refinement of the ratio of the quadrupole moments of Rb-85 and Rb-87 has also been obtained.