Wide angle X-ray diffraction studies of pure Mysore silk fibres, annealed at various temperatures at different periods of time were carried out to evaluate crystal size and lattice distortion parameters as these determine the properties of silk fibres.

Crystal sizes and lattice distortion parameters for root, pulse and cereal starch granules have been determined using observed X-ray diffraction reflections by Fourier method. Enthalpy for the formation of the lattice in root, pulse and cereal starches has been estimated and compared. It is found that the crystal size is normally high in root starch compared to pulse and cereal starches.

X-ray line broadening is found to be an effective parameter to estimate the strain associated with rare earth ion (Gd³⁺)-doped polycrystalline bismuth vanadate(Bi₂VO_5·5). The strain increases with increasing Gd³⁺ concentration. It is anisotropic and found to be maximum in (111) plane. The Curie temperature which is known to decrease with increase in the rare earth ion concentration in these compounds is correlated with increase in strain.

X-ray Laue type diffraction patterns were recorded using the image plate system at different temperatures in the nematic phase for two nematogenic compounds. Micro-orientational order parameters have been computed using different methods. These are compared with the microscopic orientational order parameters obtained from refractive index data. Higher order parameters have also been computed and compared. Distribution function at various temperatures for the two nematogenic compounds from Deutsch method has been reported.

Crystallite size and lattice distortion parameters of starches from cereals, millet, pulse, root and tuber before and after acid modification were determined by wide angle X-ray scattering (WAXS) studies. The (hkl) planes and cell parameters were obtained using a minimization program. Acid modification results in minor changes ind-spacing but there is considerable change in microcrystalline parameters, which has been reported here. Using these data, we have also estimated the changes in the mean shape of the coherent domains in terms of the shape ellipsoid in these starches for various types of acids treatment.