In Fact, I tried to understand the result (Figure 3) of a paper named "A general relationship between disorder, aggregation and charge transport in conjugated polymers", but because of some special concept I could not understand. would you please explain the result of Figure 3?
Main Question or Discussion Point
"In the case of negligible paracrystallinity, the density of states (DOS) of the 1D pi-stack depends on the amount of on-site disorder generating a Gaussian tail of states extending into the bandgap (Fig. 3a). Typical pi-stacks of conjugated polymers exhibit moderate amounts of paracrystalline disorder (g >5%; see below). Under these conditions, the DOS of the aggregate is hardly affected by on-site disorder and is determined by the amount of paracrystallinity (Fig. 3c,d). The spatial extent of the calculated wavefunctions for the disordered stack (Fig. 3e-h) shows that disorder-induced states that lie deeper into the DOS tail are increasingly localized. Even states within the originally `delocalized band' become more localized with increasing paracrystallinity. In the limit of large positional disorder (g ~10%), the distinction between band and tail disappears: a single broad distribution of localized states with a monotonically decreasing DOS extends into the bandgap, reproducing well-known results of electronic structure theory of amorphous materials34,35. In the intermediate paracrystallinity regime (g ~3-7%) we observe a coexistence of localized and delocalized states, indicating that in paracrystalline aggregates charge is transported by a mechanism where mobile charge is temporarily trapped in localized states, akin to multiple trapping and release."
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