In 1999, a little before my time, an article was published by Miller et al. in the International Journal of Biological Macromolecules, which couples results from AFM (a type of scanning probe microscopy) measurement results to SAXS patterns.

The captivating bit is that they used the height profile obtained from the AFM results to simulate (by means of Fourier transformation) a small-angle scattering pattern, which they compared to the measured SAXS scattering pattern.

My professor indicated that this is not unheard of, and that comparisons between small-angle scattering patterns and electron micrographs are performed in this fashion.

This also works the other way around. So instead of validating the scattering pattern, a micrograph can be deemed to show a representative part of the sample when the scattering pattern matches with that of a SAXS experiment. This will add more weight to the obtained micrograph and can transform it from a pretty picture to a picture representing the actual morphology.

It is important to do this, for trying to describe an entire surface by looking at a minute fraction of it (as is done with microscopy), is said to be similar to describing the surface of the earth by looking at a square millimetre. This quote is not mine, and I will find out whose it is, for it accurately defines the limitations of microscopy techniques and highlights one of the values of the scattering technique.

Nevertheless, I like the comparison by Miller et al., because it not only shows the authors to be familiar with several techniques, but also shows that they do try to verify their results obtained from one technique, with results from other techniques. In my eyes, this self-evaluating nature is not nearly being practised often enough.


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