The first sample is the PTBT polymer film deposited on a nickel surface, as it is prepared during the electro-polymerization. With prolonged electro-polymerization time, the PTBT film becomes thicker and looser, from which the outer layer is likely to fall off. The detached tances of similar polythiophene-based polymers. The simulated spectrum also features a distinct peak at 2Θ = 23.9 • , corresponding to the stacking of thiophene backbones along the short a-axis. We can also relate the stacking distance d to the unit cell parameters by The overall agreement with the simulated pattern suggests that the peaks of the PTBT-onnickel sample mainly come from crystalline phases of chains with HT-HT regularity. The fact that the experimentally measured diffractogram can only be associated with the HT-HT crystal structure again emphasizes the importance of distinguishing between different regularities. Furthermore, the absence of crystallinity in the powder sample shows that, as the PTBT film becomes thicker during electro-polymerization, its outer layers will lose most of its structural order. Only the peak at 2Θ = 23 • indicates that thiophene π-π stacking will remain to some degree in the PTBT-powder sample. In order to investigate the HH-TT system, we cut out a representative subset of the cluster's center containing N = 23 polymer chains (cf. Fig. ), red shaded area). This subsystem is then again equilibrated over 5 ns using an NPT simulation at T = 300 K. We randomly select five representative configurations for the electronic structure calculations from the last 10 ps of the equilibrated MD trajectory. The obtained MD structures are not further optimized with DFT but directly used due to the large system size. To estimate the band gap of the unordered HH-TT, we take an average over the values obtained from the five selected configurations. In Fig. , the DOS of the crystalline HT-HT phase is compared with the averaged one of the selected HH-TT systems. As can be seen, the band gap of the disordered HH-TT phase (red dashed line) is larger by 24% than that of the crystalline HT-HT aggregates (black solid line), mainly due to a shift of the conduction band edge towards higher energies. The band gap is E g = 0.72 ± 0.07 eV for the HH-TT system. When comparing the systems in Fig. , it can be seen that the polymer backbones in the HH-TT phase exhibit greater deviations from planarity than those in the ordered HT-HT phase (cf. also Fig. for a quantitative analysis), which indicates a break in conjugation in the former. It has already been observed for similar conjugated polymers that the band gap of their amorphous phases is much higher compared to that in well-ordered domains, which can be related to the reduced conjugation length along the polymer backbones of the amorphous phase. The density of states also displays a broadening of the tails near the band gap in the HH-TT system compared to the sharp band edges of the HT-HT phase. It is known that this broadening is caused by structural disorder, or so-called paracrystallinity, in the π-stacks of the system and the width of the DOS tails is a measure for the energetic disorder, that is, variations in the energy levels across the material. Furthermore, the broadening induces electronic states within the band gap of the crystalline HT-HT phase. It has been shown that disorder in the π-stacks of conjugated polymer chains causes the creation of deep tails of electronic states, which are much more localized than states inside of the bands. Thus, these states can act as traps for charge carriers, limiting their transport through the polymer. Beyond the static disorder of the HH-TT phase, dynamic disorder, that is, structural fluctuations over time, might be even more crucial in this domain as the relative position of neighboring chains will significantly influence their electronic coupling. The larger range of possible backbone dihedrals of HH-TT chains (cf.