X-ray diffraction (XRD) is a crucial non-destructive analytical technique used for characterizing materials, identifying crystalline phases, and determining atomic structures. The document outlines the principles of XRD, its historical development, instrumentation, methods, applications, advantages, and limitations. It emphasizes XRD's significance in various fields, including materials science, engineering, and pharmaceuticals.

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x-ray diffraction
By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. SYNOPSIS
Introduction
Definition
History
Principle
Instrumentation
Methods
Applications
Advantages
Limitation
Conclusion
References
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3. INTRODUCTION
X-ray diffraction (XRD) is one of the most important non-destructive
tools to analyze all kinds of matter—ranging from fluids, to powders and
crystals. From research to production and engineering, XRD is an
indispensable method for materials characterization and quality control.
X-ray diffraction techniques are used for the identification of crystalline
phases of various materials and the quantitative phase analysis subsequent
to the identification.
X-ray diffraction techniques are superior in elucidating the three-
dimensional atomic structure of crystalline solids.
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4. DEFINITION
The atomic plans of a crystal cause an incident beam of x-rays to
interfere with one another as they leave the crystal.
The phenomenon is called x-ray diffraction.
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5. HISTORY
X-ray were discovered in 1895 by the German physicist Wilhelm Conrad Rontgen
and were so named because their nature was unknown at the time.
He was awarded the Nobel Prize for physics in 1901.
1912: Max Theordor Felix von Laue (1879-1960) (U of Munich) thought that X-ray
has a wavelength similar to interatomic distances in crystals and the crystal should act
like a 3D diffraction grating.
Along with Walter Friedrich (research assistant) and Paul Knipping (PhD grad
student), he did the first diffraction experiment on CuSO4 crystal – Nobel Prize in
Physics.
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6. PRINCIPLE
X-ray diffraction is based on constructive interference of
monochromatic x-rays and a crystalline sample.
These x-rays are generated by a cathode ray tube, filtered to
produce monochromatic radiation, collimated to concentrate and
directed towards the sample.
The interaction of incident rays with the sample produces
constructive interference when conditions satisfy Bragg’s law.
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7. BRAGG’S LAW
In physics, Bragg's law, or Wulff–Bragg's condition, a special case of Laue diffraction, gives the
angles for coherent and incoherent scattering from a crystal lattice.
When X-rays are incident on an atom, they make the electronic cloud move as does
any electromagnetic wave. The movement of these charges re-radiates waves with the
same frequency, blurred slightly due to a variety of effects; this phenomenon is known As Rayleigh
scattering (or elastic scattering).
These re-emitted wave fields interfere with each other either constructively or destructively
(overlapping waves either add up together to produce stronger peaks or are subtracted from each
other to some degree), producing a diffraction pattern on a detector or film.
The resulting wave interference pattern is the basis of diffraction analysis. This analysis is
called Bragg diffraction.
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8. BRAGG’S EQUATION
nΛ = 2d sinΘ
where,
Λ = the wavelength of the x-ray
d = the spacing of the crystal layers
(path difference)
θ = the incident angle (the angle
between incident ray and the scatter
plane)
n = an integer
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9. production of x- rays
collimator
Monochromator
Filter
Crystal monochromator
Detectors
Photographic methods
Counter methods
INSTRUMENTATION
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10. PRODUCTION OF X- RAYS
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11. COLLIMATOR
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12. MONOCHROMATORS
In order to do monochromatization 2 methods are available:-
Filter
Crystal monochromator
Flat crystal monochromator
Curved crystal monochromator
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13. The x-ray intensities can be measured and recorded either by
Photographic methods
Counter methods
 Geiger – Muller tube counter
 Proportional counters
 Scintillation detector
 Solid state semiconductor detector
 Semi-conductor detectors
DETECTORS
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14. Geiger – Muller tube counter
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15. Scintillation detector
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16. Semi –conductor detectors
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18. X- RAY DIFFRACTION METHODS
These are generally used for investigating the internal structures and crystal structures of
various solid compounds.
They are
Laue’s photographic method
 Transmission method
 Back reflection method
Bragg’s x- ray spectrometer method
Rotating crystal method
Powder method
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19. Transmission Laue method
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20. Bragg’s x-ray spectrometer method
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21. Rotating crystal method
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22. Powder crystal method
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23. APPLICATION
Structure of crystal
Polymer characterization
State of anneal in metals
Particle size determination
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24. ADVANTAGE
It is a powerful and rapid technique.
Less sample required.
Unknown determination.
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25. LIMITATION
XRD also has size limitations.
It is much more accurate for measuring large crystalline
structures rather than small ones.
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26. CONCLUSION
For materials including metals, minerals, plastics,
pharmaceuticals and semiconductors XRD apparatus provide
highly accurate tools for non-destructive analysis.
The diffraction systems are also supported by an extensive
range of application software.
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27. REFERENCES
http://serc.carleton.edu>techniques
https://www.omicsonline.org.>open
http://www.rigaku.com>techniques
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