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anni
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- TL;DR Summary
- 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?
Thanks
"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."
