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X-ray Analysis Upgrades
Dr. John Dunning

Our X-ray diffraction (XRD) analysis program has improved with the addition of the 2002 edition of Jade 6.1 and a new computer. Exceptional performance is now obtained with the default settings, making it easy to select the most likely compounds from our database. The database is current through September 2001. For unknowns beyond the database, pattern indexing generates a most likely crystal structure from the angular positions of the first nine peaks.

Some alumni may remember the older X-ray fluorescence air unit which lost sensitivity for elements below calcium. We are soon to add an energy dispersive X-ray (EDX) detector attached to a scanning electron microscope. Nondestructive elemental analysis will be possible as no sample coating will be involved. Historical specimens, thin films, minerals in intact rocks, and stamps are some of the samples we will be able to analyze. The combination of XRD and EDX forms a powerful analytic tool.

Visitors are encouraged to stop by our laboratory in Darwin 33. We usually have something interesting being analyzed. The next offering of the X-ray analysis course, Physics 384, will be in the Fall of 2003. This laboratory is a joint endeavor with Geology.