Deconvoluting Patterson.

The Patterson function, P(u), is useful in many crystallographic applications, including experimental phasing, molecular replacement and the exploration of non-crystallographic symmetries. P(u) is defined as the autocorrelation of the electron density. Autocorrelation is often an unfamiliar concept for students of biological or biomedical fields of study. I present a freely available animated PowerPoint slide deck featuring 1D electron density plots and the corresponding autocorrelation resulting in the Patterson function that is readily interpretable as an interatomic distance map. The animation makes it easy to grasp the concept of autocorrelation in an intuitive manner.