Fig. 6. (a) Potential difference, computed in the hetero-vacancy case, with and without the gated field projected along the z-axis. (b) Induced charge density projected along the z-axis. (c) Representation of charge density for non-uniformly distributed vacancy case (S–Mo,1,1–1). (d) Representation of charge density for the uniformly distributed vacancy case (S–Mo,1–2,1–1).