Fig. 2: Formation energy of VS in MoS2 referenced to the standard states as a function of Fermi energy.
From: Quantum point defects in 2D materials - the QPOD database

Calculated formation energy (blue, solid) as a function of the Fermi energy plotted together with the CTL (blue, dotted). The orange solid lines (orange dotted lines) highlight the PBE-D calculated formation energy (CTL of (0/−1) and (0/1)) of VS in MoS2 taken from Komsa et al.56.