research papers
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 β-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 (110) {010}, 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.