Comparing 2D Xray diffraction peaks
After entering five atoms, the user can highlight one of the atoms,
(orange) and then add a "test atom" in white. When you push "New Xray",
you get a second diffraction peak, this one excludes the highlight atom
from its calculations and replaces it with the white test atom.
At this point, You can either "Accept" or "Reject" the new atomic position.
And this goes on until you get tired of it. Pretty neat, huh? You can
always begin again via the "Restart" button, or move on to some other
place on the web.
X ranges from 0 to 450.
Y ranges from 0 to 300.
The source code