to the basis set used.

![Electronic densities of states for tetragonal systems with 0 and 1/4 ML doping, calculated using the DZP (<span style="font-variant:small-caps;">siesta</span>) basis set. The Fermi level is indicated by a solid vertical line with label. 50 meV smearing was applied for visualization purposes.[]{data-label="fig:eDOS"}](d1dzpedos){width="\linewidth"}

The Fermi energy exhibits convergence with respect to the amount of cladding, as reported above. It is also notable that the eDOS within the bandgap are nearly identical regardless of the cell length (in $z$). This indicates that layer-layer interactions are negligibly affecting the occupied states, and therefore that the applied “cladding” is sufficient to insulate against these effects.

Electronic width of the plane {#sec:width}
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In order to quantify the extent of the donor-electron distribution, we have integrated the local density of states (LDOS) between the VBM and Fermi level and taken the planar average with respect to the $z$-position. Figure \[fig:d1dzprho\] shows the planar average of the donor electrons (a sum of both spin-up and spin-down channels) for the 80-layer cell calculated using the DZP basis set. After removing the small oscillations related to the crystal lattice to focus on the physics of the $\delta$-layer, by Fourier transforming, a Lorentzian function was 