Fig. 2. Hierarchically oriented crystallization of linear short peptides.

a | Scanning electron microscopy images of hexagonal peptide microtubes formed by the high-order assembly of diphenylalanine (FF) nanotubes¹³. b | Laminated crystal structures resulting from tert-butoxycarbonyl diphenylalanine (Boc-FF) high-order self-assembly that results in mechanical flexibility⁷. c | Atomic force microscopy (AFM) image of acetylated KLVFF microcrystals exhibiting a lamellar structure²⁷. d | Schematic illustration of the oriented organization of nanocrystals that leads to the formation of hollow DL-alanine mesocrystals³⁴. e | In situ AFM images of MoSBP1 assemblies constrained on the MoS₂ (0001) surface (left) showing parallel rows with a periodicity of 4.1 nm (right)⁴¹. NP, nanoparticle. Part a is adapted with permission from REF.¹³, Wiley-VCH. Part b is adapted with permission from REF.⁷, Wiley-VCH. Part c is adapted with permission from REF.²⁷, ACS. Part d is adapted with permission from REF.³⁴, ACS. Part e is adapted with permission from REF⁴¹, AAAS.