Introduction to the program CMWP-fit
CMWP-fit is a computer program developed for the determination of microstructural
parameters from diffraction profiles of materials with cubic or hexagonal
crystal lattice. The whole measured powder diffraction pattern is fitted by
the sum of a background function and ab-initio theoretical functions for
size and strain broadening.
By giving the list of the relevant base points of the physical background,
the background function is determined as the interpolated cubic spline
corresponding to the specified base points. In the calculation of the theoretical
functions it is assumed that the crystallites have lognormal size distribution
and the strain is caused by dislocations. Strain and size anisotropy is
taken into account by the dislocation contrast factors and the ellipticity
of crystallites. The fitting procedure provides the median and the variance
of the size distribution and the ellipticity of crystallites, and the
density and arrangement of dislocations.
This procedure is similar to the method of Multiple Whole Profile fitting.
For more details about the MWP method, please visit:
Multiple Whole Profile fitting Main
Page. However the CMWP method is more sophisticated, so you should use
the CMWP method when possible.