Figure 1: SAD patterns of a nanocrystalline MgH2 particle.
From: Comments on ”Evidence of the hydrogen release mechanism in bulk MgH2”

The pattern in (a) was recorded under low dose conditions after irradiating the sample area for no longer but a few seconds. It shows both Mg and MgH2 diffraction spots. (b) After an exposure over 60 s, all MgH2 diffraction spots have vanished, and new Mg diffraction spots occur in the pattern.