Fig. 1: Exemplary density of states for different doping concentrations.
From: Critical charge transport networks in doped organic semiconductors
a Amorphous material, i.e. with point-molecules placed randomly, but with a minimal distance of 0.5 nm. b Tetragonal lattice using the lattice spacings of ZnPc (see Supplementary Table 1 for details). The occupied states are shown in blue. With increasing doping concentration, the DOS broadens for both structures, as some states get raised and some get lowered by the one or the other type of charge. In the light doping regime, the peak position of the unoccupied DOS stays constant, due to the equal amount of positive and negative charges. Note that for the tetragonal lattice, an additional peak in the unoccupied DOS arises due to the the neutral ZnPc in the Coulomb potential of the, for n-doping, negatively charged ZnPc next to it and the positively charged dopant two places away (we do not account for a different shape of the dopant molecule). The doping concentrations are given in molar percentages and the plots are offset vertically for clarity.
