Demonstrations

X-ray Diffraction - Optical Analog

Code Number :	7A60.24
Disclaimer:	Reprinted by permission of Dick Berg, University of Maryland, for use on this website. The demonstrations contained and referenced herein are listed for the purposes of cataloging and describing physics demonstrations which should be conducted only under the direction of a trained instructional support professional or physicist. These demonstrations are not presented for the purpose of being conducted by persons unconnected to this Facility and/or persons not consulting with or being supervised by the recognized instructional support professional or physicist and his/her staff. The University is responsible only for those demonstrations carried out using its own equipment using established safety and scheduling policies, and bears no responsibility for those choosing to use this source material for their own purposes. All demonstrations described and contained herein are public domain, and can also be found in reference materials in libraries, bookstores, and electronic sources. Further information regarding legal liability in use of demonstrations and labs will be found on the web site Injuries in School/College Laboratories in USA. The University of Iowa Disclaimers: University of Iowa Disclaimer All Rights Reserved..
Condition :	Good
Principle :	Two-Dimensional Gratings, Crystal Structures
Area of Study :	Optics, Modern Physics
Equipment :	Helium-neon laser (2 to 5 mw.), Optics bench, Optical Transform Slides - Unit Slide, Discovery Slide, VSEPR Slide, Plane Group Slide.
Procedure :	An optical analog of x-ray diffraction is to use the slides that have crystal pattern reductions and a laser. Different crystal structures will give different Fraunhofer diffraction patterns.

References

Cyril Isenberg, "Laser Diffraction Experiments with Pseudoliquids and Pseudosolids", TPT, Vol. 38, # 7, Oct. 2000, p. 411.

Se-yuen Mak, "Gratings for Simulation of Laue Crystal Diffraction", TPT, Vol. 32, # 9, Dec. 1994, p. 539.

Sir Lawrence Bragg, "The History of X-Ray Analysis", TPT, Vol. 3, # 7, Oct. 1965, p. 295.

Qun Shen, Quan Hao, and Sol M. Gruner, "Macromolecular Phasing", Physics Today, March 2006, p. 46.

Kathryn D. Burch et al., "Optical Simulation of Low-Energy Electron Diffraction Patterns," Am. J. Phys, 237, Vol. 53, No. 3, (March 1985).

George R. Mitchell, "The Reciprocal Lattice - A Demonstration", AJP, Vol. 46, (5), May 1978, p. 574.

"Optical Transform Kit," Institute for Chemical Education, University of Wisconsin - Madison.

Ellis, Geselbracht et al., Teaching General Chemistry: A Materials Science Companion, "Chapter 4: Determination of Structure Using Diffraction Data," p. 77.

Mail Questions and Comments to: Dale Stille