Influence of Point Defects and Dislocations on the Line Shape of Nuclear Magnetic Resonance Signals

The quadrupolar part of the line shape of a NMR signal is determined by lattice imperfections in the case of cubic crystals. This quadrupolar shape function is presented under the assumption of randomly distributed point defects, dislocation dipoles, and dislocations. Experimental quadrupole shapes were obtained by a line shape analysis of the NMR wide‐line signal and the spin echo signal in the case of different alkali halide crystals. The resulting quadrupolar lines can be compared with the calculated functions. The comparison shows an agreement of the measured shape with the point defect model in the case of undeformed crystals, whereas in the case of deformed crystals the dislocation model is valid.