Form factor of an N-layered helical tape and its application to nanotube formation of hexa-peri-hexabenzocoronene-based molecules

Self-assembled helical supramolecular structures are widely found in nature and have also been observed in several systems based on synthetic amphiphiles. Such structures often exhibit interesting properties that can be utilized in different nanotechnological applications. Based on previous work concerning the form factor of helical filaments with a finite cross section, the present work gives the helical form factor generalized for a tape containing N layers. The presented form factor is applied to the characterization of an intermediate structure obtained during the formation of self-assembled graphitic nanotubes. The structure was modeled as a centrosymmetric bilayer containing five layers including a structure factor. These results have been compared with that obtained using a model based on polydisperse cylinders, and it is shown that the full description with helical model and structure factor is the superior one.