The interdependence of the
crystallite size D and lattice strain Iu (Fig.
Using the Rietveld refinement and Warren-Averbach method [24, 25] in the frame of MAUD software [31], a detailed analysis of XRD profiles can be performed leading to the determination of phase composition in addition to structural and microstructural parameters for each phase, such as lattice parameters (a, b, c), the average
crystallite size <L>, microstrain [<[[epsilon].sup.2]>.sup.1/2], and stacking fault probabilities (SFP).
The average
crystallite size and crystal phase of calcium carbonate obtained from seashells were determined using X -ray diffraction analysis.
The average sizes of the
crystallites, determined qualitatively by application of the Scherrer equation, were on the nanoscale.
From Fig.2 it is revealed that as the sintering temperature increased from 60 to 800[degrees]C, several of the HA peaks become more distinct and narrower signifying an increase in the
crystallite size and crystallinity confirming the important role of sintering.
As seen in Figure 1, T1W exhibits small
crystallite size of anatase phase.
The results of the structural studies revealed that all samples had
crystallites in the nanosize range; [Cu.sup.2+] addition into the Ti[O.sub.2] increases the
crystallite size which maybe due to the replacement of [Ti.sup.4+] ions by [Cu.sup.2+] ions which have a higher ionic radius.
In terms of the FWHM, all samples experienced increase in
crystallite sizes after annealing, with the samples grown at 1445 mV and 1450 mV showing the highest
crystallite size of 63.02 nm.
X-ray diffraction shows that the synthesized ZnO nanoparticles have hexagonal crystal structure with an average
crystallite size of 29 nm.
Where D is
crystallite size (in nm), [lambda] is the radiation wavelength (for CuK[alpha] radiation, [lambda] 1.5406[Angstrom]), [theta] is the diffraction peak angle and [beta] is the broadening of the line ("half width") measured at half its maximum intensity (in radians).