Why X-rays are used to study the crystal structure?
It is well known that X-rays can penetrate solids since these are very high energetic radiations of very short wavelength (1A°). In a crystalline solid the atoms are very closely
distributed in crystal planes.The crystal planes,thus form a three dimensional slit system with a spacing (1A°). Due to this fact X-rays get strongly diffracted from various crystal planes. By analysing the diffraction pattern of a crystal its internal atomic arrangement can be determined.
Hence W.H Bragg explained the phenomenon of X-ray diffraction from a single crystal . Hence this was the reason for using X-rays for the study of crystal structure.