Samples in this technique are mounted on a goniometer prior to being bombarded with light to form an interference pattern. For 10 points each:
[10e] Name this technique that measures the diffraction of high-energy light to determine the structure of macromolecules. Photo 51 was obtained by Rosalind Franklin using this technique.
ANSWER: X-ray crystallography [or X-ray diffraction; or XRD; prompt on crystallography or diffraction]
[10m] Patterson functions are used to solve a “problem” named for this quantity that arises because CCDs in X-ray crystallography machines only measure intensity. A form of this quantity named for Michael Berry causes the Aharonov–Bohm effect.
ANSWER: phase [accept phase problem or Berry phase]
[10h] Once the phase problem has been corrected, chemists can calculate how well their predictions match a chemical’s actual structure using this parameter. This parameter quantifies the differences between the observed and calculated structure factors.
ANSWER: R-factor [or residual factor or reliability factor or the R-value or RWork]
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