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.