A published new theory of X-ray diffraction is wrong
What is it about?
In order to explain specific phenomena in powder X-ray diffraction, some ten years ago a modified theory for X-ray diffraction was proposed. After much digging, we found a major conceptual mistake in the new theory. This mistake led to features that seemed surprising and interesting, but need to be discarded.
Why is it important?
X-ray diffraction has been used since 1915 and the theory has stood the test of time, so proposing a ‘new theory for X-ray diffraction’ seemed a bold step. Science makes progress by challenging earlier theories, but in this case we found the challenge has to be rejected. It is important that we have now a confirmation that the classic theory can still be used. In addition, the manuscript summarizes the main features of the classic theory for X-ray scattering and describes in detail the scattered intensity distribution in all directions, not only at the strong bulk Bragg peaks. This shows that almost always the residual intensity can be ignored.