Chapter 10
Overview: Fitting diffraction patterns
There are four key aspects for obtaining a good fit to a powder diffraction pattern in
a Rietveld refinement:
- Fitting the background, which means reproducing the slowly-varying
parts of the diffraction pattern, that arise from instrumental artifacts as
well as non-Bragg scattering from the sample (Chapter 11),
- Fitting the peak positions, which are determined by lattice parameters
and instrumental calibration/corrections must be in the correct places
(Chapter 12).
- Reproducing the peak intensities, as determined from the crystal structure
model as well as corrections such as preferred orientation and extinction
(Chapter 13).
- Matching the shapes of the peaks, as this must reproduce the broadening
effects of both the diffraction instrument and effects from the sample
(Chapter 14).
Each of these aspects of fitting will be discussed in the following chapters.