²³Na spin echoes in NaCl single crystals

Abstract

With the object of estimating dislocation densities and orientations in NaCl, a series of single crystals was prepared with up to 10% plastic deformation along the [001] axis. The 23Na nuclear magnetic resonance was examined at room temperature using continuous wave, free induction decay and spin-echo methods. It is shown that using the spin-echo technique it is possible to separate out the quadrupole broadening from the magnetic dipole broadening and also to distinguish between the dipole broadening due to the central component of resonance and that due to the satellites. Using the continuous wave and free decay techniques this is not possible. Unfortunately the poor signal to noise ratio obtainable in the present experiments prevented a detailed analysis of the measurements, but an approximate treatment yielded useful results. Dislocation densities were obtained for the different crystal samples.