Nuclear quadrupole interactions in liquid and solid metals

The nuclear quadrupole relaxation time in liquid metals is calculated, assuming free-ion cores interacting by an oscillatory screened potential, and whose positions in the liquid are described by the time-dependent pair distribution function of Oppenheim and Bloom. The relaxation time depends on two- and three-particle correlation functions, and the three-particle correlations are treated by means of the superposition approximation. Uncertainties in the antishielding factor and the potential oscillations are eliminated by using the experimental value of the quadrupole coupling constant in the solid. Detailed calculations are performed for Ga and In, and good agreement with the observed relaxation time is obtained if the three-particle terms are neglected. The calculated three-particle terms are not negligible, and it is suggested that the superposition approximation introduces serious errors.