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Chapter III CHN Analysis, FT IR …..
assigning indices to the reflections. Apart from these, cold work, recovery and
re-crystallization are readily recognized by their effect on the powder patterns.
Basically, this method involves the diffraction of monochromatic X-ray by a
powdered specimen. Usually ‘monochromatic’ means the strong characteristic
K component of the filtered radiation from an X-ray tube operated above the K
excitation potential of the target material. The “Powder” can mean either an
actual, physical powder held together with suitable binder or any specimen in
polycrystalline form. Since single crystals are not always available, this
method is more suitable for structural determination of various substances.
The powder method is also known as the Debye-Scherrer method.
When X-ray is incident on the crystalline powdered sample, it gets diffracted
in form of cones, which is exhibited in figure (3.11 b). The broad applications
of powder XRD are summarized in the following points:
Figure:3.11a Set up for powder XRD.
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