Figure 4
From: Using defects to store energy in materials – a computational study

Energetics of defect formation and recombination, shown for a FP defect consisting of a vacancy (red empty circle) and interstitial (red atom) pair. The states involved in the recombination reaction are the FP defect (left), transition state (center) and pristine lattice (right). The FP formation energy E F and the activation barrier E A are also shown. The energy E A needs to be provided for FP recombination.