X-Ray Diffractometry XRD

 X-Ray Diffractometry (XRD):

Principle:  In this technique the primary X-rays are made to fall on the sample substance

under study. Because of its wave nature, like light waves, it gets diffracted to a certain angle.

This angle of diffraction, which differs from that of the incident beam, will give the

information regarding the crystal nature of the substance. The wavelength of the X-rays can

be varied for the application by using a grating plate.

Instrumentation :  It consists of X-ray tube for the  source, monochromator and a rotating

detector.

Applications : The diffraction of X-rays is a good tool to study the nature of the crystalline

substances. In crystals the ions or molecules are arranged in well-defined positions in planes

in three dimensions. The impinging X-rays are reflected by each crystal plane. Since the

spacing between the atoms and hence the planes can’t be same or identical for any two

chemical substances, this technique provides vital information regarding the arrangement of

atoms and the spacing in between them and also to find out the chemical compositions of

crystalline substances. The sample under study can be of either a thin layer of crystal or in a

powder form. Since, the power of a diffracted beam is dependent on the quantity of the

corresponding crystalline substance, it is  also possible to carry out quantitative

determinations.