Figure 1.

(a) Schematic of a diffraction pattern. The phase of each reflection is represented by color and its intensity is represented by the size of the reflection. Reflections B, C and D are highlighted with black circles. (b, c, d) The spatial frequency components of the electron density encoded by structure factors which correspond to the circled reflections B, C and D, respectively, in (a). The outline of the unit cell is shown as white dashes. Reflections farther from the origin exhibit a higher spatial frequency (for example reflection D). Brighter reflections correspond to higher-amplitude spatial frequency (for example reflection C). (e) Summing over all components results in the electron density of the sample.