Nuclear spin relaxation in liquid mercury and the quadrupolar relaxation mechanism

Abstract

Reports the measurement of the linewidths of the 199Hg and 201Hg nuclear magnetic resonances in liquid mercury from 240K to 420K. From these data the authors have extracted the longitudinal relaxation rates, R1. For 199Hg, which has a nuclear spin of 1/2, this rate is determined solely by the magnetic dipolar interaction with the conduction electron spins. However 201Hg has a nuclear spin of 3/2 and of large quadrupole moment. Its relaxation rate is therefore a composite sum of the dipolar rate, R1m, together with an additional quadrupolar contribution , R1q. This is reflected in the results for 201Hg where R1, which is approximately 3.5*104 s-1 at 300K, diminishes slowly with increasing temperature. Both R1 for 199Hg and the extracted R1m for 201Hg may be explained by the hyperfine interaction with the s-like part of the conduction electron density together with a small contribution from other sources.