X-RAY Diffraction 1.Introduction 2.What is X-Ray? 3.Basic principle 4.Instrumentation 5.Bragg’s Law and X-Ray 6.Diffraction 7.Applications INTRODUCTION: X-rays are electromagnetic waves having wavelength in range of 0.1-100Å. X-rays used in diffraction techniques have typical wavelength of 0.5-1.8Å. X-rays were discovered by Wilhelm Roentgen who called them X-rays and it is also called as Roentgen rays. BASIC PRINCIPLES: In an atom, the electrons are arranged in layers or shells, like K-shell L-shell M-shell N-shell. When the atom is bombarded with an electron, eject one of the electron from the inner shell. The electrons migrate from the outer shell to the inner shell to fill the gap with higher energy. A quantum of radiation (X-rays) is emitted corresponding to this transition, time scale is approximately 10-12-10-14 sec. Emitted radiation is called X-rays. X-RAY DIFFRACTION PRINCIPLE: X-ray diffraction is based on constructive interference of monochromatic X-ray and a crystalline sample. These 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. INSTRUMENTATION: 1.X-ray tube 2.Collimator 3.Monochromator 4.Filter 5.Crystalmonochromator 6.Detectors APPLICATION OF X-RAY DIFFRACTION: Identification of single-phase materials, minerals, chemical compounds and ceramics. Identification of multiple phase in microcrystalline mixture(rocks). Determination of crystalline size and shape. Crystallographic structural analysis and unit cell calculation from crystalline materials. Particle size determination-Spot counting methods.

1. X-RAY DIFFRACTION

2. OUTINE OF X-RAY DIFFRACTION
■ Introduction
■ What is X-Ray?
■ Basic principle
■ Instrumentation
■ Bragg’s Law and X-Ray diffraction
■ Applications

3. INTRODUCTION
■ X-rays are electromagnetic waves having wavelength in range of
0.1-100Å.
■ X-rays used in diffraction techniques have typical wavelength of
0.5-1.8Å.
■ X-rays were discovered by Wilhelm Roentgen who called them
X-rays and it is also called as Roentgen rays.

4. REGION OF X-RAYS

5. BASIC PRINCIPLE
■ In an atom, the electrons are arranged in layers or shells,
like
K-shell
L-shell
M-shell
N-shell

6. Contd…
When the atom is bombarded with an electron, eject one of
the electron from the inner shell.
The electrons migrate from the outer shell to the inner shell
to fill the gap with higher energy.
A quantum of radiation (X-rays) is emitted corresponding to
this transition, time scale is approximately 10-12-10-14 sec.
Emitted radiation is called X-rays.

7. X-RAY DIFFRACTION PRINCIPLE
■ X-ray diffraction is based on constructive interference of monochromatic
X-ray and a crystalline sample.
■ These 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.

8. INSTRUMENTATION
■ X-ray tube
■ Collimator
■ Monochromator
• Filter
• Crystal monochromator
■ Detectors

9.  X-ray tube:
High velocity of electrons bombarded on target metal, X-rays are produced.
 Collimator:
Closed metal plates separated by small gap.
Use is to produce narrow beam.
 Monochromator:
Absorb the undesirable radiations and allows required wavelength to pass.
INSTRUMENTATION

10.  Detectors:
Photographic methods
Counter methods
Types:
■ Geiger-Muller counter
■ Proportional counter
■ Scintillation counter
■ Solids state semiconductor counter
INSTRUMENTATION

11. INSTRUMENTATION

13. The relationship describing the angle
at which a beam of X-rays of a
particular wavelength diffracts from a
crystalline surface was discovered by
William Bragg and Lawrence Bragg
and is known as Bragg’s Law.
BRAGG’S LAW AND DIFFRACTION

14. APPLICATION OF X-RAY DIFFRACTION
■ Identification of single-phase materials, minerals, chemical compounds and
ceramics.
■ Identification of multiple phase in microcrystalline mixture(rocks).
■ Determination of crystalline size and shape.
■ Crystallographic structural analysis and unit cell calculation from crystalline
materials.
■ Particle size determination-Spot counting methods.

15. XRD pattern of CuO NPs

16. Recommended book
■ Biochemistry Laboratory: Modern Theory and Techniques
■ Rodney Boyer (Hope College)
■ Second Edition
■ Chapter 7: Spectroscopic Analysis of Biomolecules
■ E. (X-ray crystallography)

18. THANK
YOU