Optical Transform Kit

 

Code Number: 7A60.24

Demo Title: X-ray Diffraction - Optical Analog

Condition: Good

Principle: Two-Dimensional Gratings, Crystal Structures

Area of Study: Optics, Modern Physics

Equipment: 

Helium-neon laser (2 to 5 mw.) or Laser Pointer, 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.

You can also make your own slides by using a piece of cellophane tape and Lycopodium powder, or letting some microspheres dry on a microscope slide and then hitting them with a laser.

References:

  • F. Logiurato, L.M. Gratton, and S. Oss, "Optical Simulation of Debye-Scherrer Crystal Diffraction", TPT, Vol. 46, # 2, Feb. 2008, p. 109.
  • 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.
  • Peter Russo, Alfred D. Brothers, "Powder Diffraction Patterns on the Tel-X-Ometer 80", AJP, Vol. 50, # 1, p. 89, Jan. 1982.
  • 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.
  • Ronald Bergsten, "Optical Crystals", AJP, Vol. 42, #2, Feb. 1974, p. 91.
  • Johanna Miller, "Femtosecond Snapshots Capture Atomic Motion in a Powdered Solid", Physics Today, Sept. 2010, p. 13.
  • Qun Shen, Quan Hao, and Sol M. Gruner, "Macromolecular Phasing", Physics Today, March 2006, p. 46.
  • "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.