Crystallography Matters!

Resources for crystallographic education

Anomalous dispersion of X-rays in crystallography

The contribution of resonance or dispersion effects to the atomic scattering factors

S. Caticha-Ellis

Instituto de Fisica 'Gleb Wataghin' Universidade Estadual de Campinas C.P. 1170 - Campinas - S.P. Brasil

Teaching aims

To lay a foundation for the understanding of the phenomenon of anomalous dispersion and its significance and importance now that very accurate methods of measuring X-ray intensities are available.


This is suitable as an introductory text in a postgraduate course designed for students who are already fairly well acquainted with X-ray crystallography.

Background required

A fairly thorough knowledge of crystallography and of X-ray diffraction principles and techniques is really necessary for a proper understanding of this article.

Practical resources

No specific resources are needed - though actual experience of X-ray photographs exhibiting anomalous dispersion effects would be an advantage.

Time required for teaching

This is a fairly 'meaty' course which would require five or six hours for full discussion and assimilation.