Phase determination

This paper is not particularly interesting in itself. It outlines how to determine the phase of a XRD beam and determine the crystal structure of the crystal. It essentially removes the monochromatic approximation from the problem, assumes a finite spectral width, then uses the Young's double slit apparatus to observe the phase information deduced from the interference patterns.

Solution of the Phase Problem in the Theory of Structure Determination of Crystals
from X-Ray Diffraction Experiments

There are three things about it I find interesting. First, this has been an outstanding "problem" for 100 years! The second is that it is one of the few examples I have seen where introducing "real world" complications (non-ideal eg. finite spectral width) actually simplifying the calculation. I should disclose the fact that I usually read papers with little experimental impact: ideal systems and first principles papers. It is also kind of cute that it is only 2 pages of work including some fairly basic equations. This paper shows that "standard" models can sometimes be altered slightly (albeit in usually less obvious ways) and solved.