Rocking Curve

RC measurement reveals broadening of the diffraction peaks. The increase in the peak widths can be caused by:

Mosaicity (misorientation of crystallites)

Strain

Limited layer thickness

Typically XRD peak width is quantitatively described by Full-Width-at Half-Maximum (FWHM). From RC measurement it is impossible to separate mosaicity (variation in w) and lattice strain (variation in w/2q). These effects can be separated by analyzing Reciprocal Space Maps (RSM).