X-ray crystallography

If you are looking for a short course on X-ray crystallography, you won't find it here.

Purdue Chemistry X ray department Apparently you can submit samples and they will solve a structure for a flat fee of $400 - like buying a pound of hamburger.

Units of measure have style and fashion like anything else. When I studied X-ray crystallography, the fashionable unit was the angstrom (10^-10 meters), but now the nanometer (10^-9 meters) seems to be in vogue. There are 10 angstroms in a nanometer. Copper targets provide a handy X-ray source and are often used, with a filter that isolates the K-alpha line, which has a wavelength of 1.54 angstroms (0.154 nanometers). Calcium has an atomic radius of 1.97 angstroms. The Cl- ion has a radius of 1.81 angstroms.

Note that visible light has a wavelength of 3000-7000 angstroms. Another unit that comes up is the picometer (pm) which is 10^-12 meters. There are 100 pm per angstrom, and 1000 pm per nm.

Google indexed a bunch of power point course notes from the Purdue Chemistry deparment, which I have stashed here:

It looks like the Purdue course used the book "Crystal Structure Determination" by Werner Massa.

Also from POSTECH in Korea


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