Coupling between spatial and angular variables in surface X-ray diffraction: effects on the line shapes and integrated intensities

A general integral form of the integrated intensity of a rocking scan in z-axis type surface X-ray diffraction measurements is presented, which allows an accurate derivation of the structure-factor amplitude. The intensity line shape is stimulated on the basis of the in-plane distribution of rods, by considering the specific scattering geometry of any point of the illuminated sample surface with respect to the detector slit setting.