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![Page 1: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/1.jpg)
X-Ray Diffraction as a Materials Characterization Technique
By: Omar AlshehriWaterloo, ONSpring 2010
![Page 2: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/2.jpg)
Outlines
• History.• Must-have basics.• How x-rays are generated?• How characterization is done?• Applications.• The $1 x-ray source.• Conclusion.
![Page 3: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/3.jpg)
History
• Discovered accidently in November 8th
1895 by Wilhelm Roentgen.• He was awarded the 1st Nobel Prize in
physics [1].• In 1912 Max von Laue invents x-ray
diffraction.• William Lawrence Bragg figured out how
to use x-rays to determine the crystal structures of materials.
Source: [8]
Source: [7]
Source: [7]
![Page 4: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/4.jpg)
Must-Have Basics
• X-ray is a form of electromagneticradiation.
• The energy associated with x-ray is as follows: eV/photon.
• The wavelengths range is0.001<λ<10 nm. NO HARD RULESFOR DETERMINING THIS RANGE [2].
• Therefore, if we plug in λ=0.1 nmwe will get an energy of12,400 eV/photon. How huge is it?
![Page 5: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/5.jpg)
Must-Have Basics (cont.)
Inner shell electron.Nitrogen atom
n=1
n=α
The ionization energy=668 eV.
The ionization energy, the energy to nock out an electron to the vacuum level, for the inner most electrons of nitrogen is 668 eV. Compare it with the 12,400 eV/photon for the 0.1 nm wavelength’s x-ray!!! Very huge [2].
![Page 6: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/6.jpg)
How X-Rays are Generated
• There are three methods to generate x-ray [3]:1- X-ray tube.2- Synchrotron radiation.3- 1 dollar source [4].
Most common in laboratories.
![Page 7: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/7.jpg)
How X-Rays are Generated (cont.)
Filament (Cathode)
Electrons
Target (Anode)
Vacuum Chamber
X-ray
The efficiency of energy conversion from thermoelectrons to x-rays is exteremely low 0.1%
Current
![Page 8: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/8.jpg)
How X-Rays are Generated (cont.)
Filament (Cathode)
X-ray
Target atom: Cu or Mo atom
Emitted electron
Ray or Rays?
![Page 9: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/9.jpg)
How Characterization is Done [5,7]
?
![Page 10: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/10.jpg)
Image Plate~$350K
![Page 11: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/11.jpg)
Benzene Snowflake
Isolated“Benzenes”
Look for e-density onevenly spaced planes.
(or near)
![Page 12: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/12.jpg)
Benzene Snowflake
Isolated“Benzenes”
Closer-spacedplanes give
higher angles.
Look for e-density on (or near)evenly spaced planes.
![Page 13: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/13.jpg)
“Direct” or “Diffraction” or “Real” Space “Reciprocal” Space
Crystal Diffraction Photo
“Unit Cell” Structure Fuzzy Pattern
Crystal Lattice Viewing Holes
Decreasing Spacing Increasing Spacing
How Characterization is Done? (cont.) [5]
![Page 14: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/14.jpg)
How Characterization is Done? (cont.) [6]
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Conclusions
• X-ray diffraction is a powerful technique but with many precautions as has harmful radiations.
• As x-ray diffraction has many capabilities, it has limitations that prevent its application.
• Day by day, science is proving it self to be simpler and cheaper than we pretend it!
![Page 17: X-Ray Diffraction as a Materials Characterization Technique By: Omar Alshehri Waterloo, ON Spring 2010 oalshehri@ksu.edu.sa.](https://reader037.fdocuments.net/reader037/viewer/2022110207/56649d8c5503460f94a74202/html5/thumbnails/17.jpg)
References• 1- nobelprize.org• 2- Donald Sadoway, 3.091 Introduction to Solid State Chemistry, Fall 2004. (Massachusetts Institute of
Technology: MIT OpenCourseWare). http://ocw.mit.edu (accessed 07, 20, 2010). License: Creative Commons Attribution-Noncommercial-Share Alike.
• 3- Materials Characterization Techniques. By: Zhang, Sam, Li, Lin, and Kumar Ashok. CRC press, 2008.• 4- http://www.nature.com/nature/videoarchive/x-rays/• 5- https://webspace.yale.edu/chem125_oyc/125/LectureSlides/Lect06timed.ppt• 6- http://www.eserc.stonybrook.edu/ProjectJava/Bragg/• 7- https://webspace.yale.edu/chem125_oyc/125/LectureSlides/Lect05timed.ppt• 8- Wikipedia.com