Where 𝑛 is the number of the repeat unit, 𝑣 𝑛 is the backbone tangent vector of repeat unit 𝑛 and 𝑛 𝑝 is the persistence length in terms of repeat units. The persistence length in terms of length 𝑙 𝑝 is determined by multiplying 𝑛 𝑝 by the length of the PII-2T repeat unit which was determined from DFT simulations to be ~1.8 nm.