Modelling dislocation-induced anisotropic line broadening in Rietveld refinements using a Voigt function. II. Application to neutron powder diffraction data

In paper I [Wu et al. (1998). J. Appl. Cryst. 31, 356-362] an approach was developed to the problem of modelling dislocation-induced X-ray or neutron-diffraction-line broadening. This paper applies those findings to the Rietveld refinement of the neutron powder diffraction profiles of deuterium-cycled LaNi5 and beta-PdD0.66. These interstitially modified materials exhibit, respectively, strong and weak anisotropic strain broadening. The broadening in LaNi5 is consistent with a dislocation slip system a/3[(2) over bar 110]{0 (1) over bar 10}, in agreement with transmission electron microscopy studies. In PdD0.66 the model predicts a regular distribution of screw dislocations, which remains to be confirmed by other techniques.