ABSTRACT
Diffraction takes place when a wave interacts with a lattice whose dimensions are of the same order of magnitude as that of the wavelength of the wave. The lattice scatters the radiation, and the scattered radiation from one point interferes with the radiation from others so as to either enhance the amplitude of the radiation (constructive interference), or to reduce it (destructive interference) (Fig. 1). The pattern of constructive and destructive interference yields information about molecular and crystal structure.
