The C8S3 CG model was also used for simulating preformed nanotubes of different size and measuring their structural features. All simulated nanotubes maintained their tubular structure along the trajectories (1 µs). A snapshot from the final step of nanotube simulation is shown in Figure . The diameters of the designed systems ranged from 12 to 17 nm, close to the reported experimental values in the literature for the nanotube diameter vary from 13 to 17 nm . Previous atomistic MD studies showed that preformed nanotubes with different diameter can be stable, as long as the nanotube thickness and the initial monomer arrangement is reasonable . All systems were constructed with an initial double-wall thickness of ∼2.5 nm, which remained roughly the same in all simulations. The values for the final dimensions of the simulated nanotubes are reported in Table of the Supplementary Information. Among the potential arrangements, only the brickwork formation was stable with our CG model. Attempts with the herringbone formation resulted in deformed nanotubes during the beginning of the production phase (250-500 ns). Snapshots of deformed nanotubes are included in Figure of the Supplementary Information. Last but not least, we used the C8S3 CG model to simulate a C8S3 bundle, in other words, several nanotubes grouped together (see Figure ). Bundles are the result of nanotube agglomeration, and they are formed when samples of C8S3 nanotubes are stored for several weeks at room temperature . The bundles can be either straight or twisted, but the driving forces of this morphological difference are unknown. Despite the small defects in the final structure, the overall shape of the bundle was maintained. The final structure looks quite similar to the suggested model from Electron Microscopy experiments . In our case, the centre-to-centre distance is 8 nm, which is slightly smaller when compared to the experimental measured distance (10±1 nm).