Fig. 2: Self-assembly of cube-shaped assembly (nanocube) from gear-shaped amphiphiles (GSAs).

a Chemical structures of C_2v- and C_S-symmetric GSAs, 1²⁺ and 2²⁺. b Schematic representation of the [1₆]¹²⁺ nanocube in analogy to the Earth. c The geometry net of the [1₆]¹²⁺ nanocube. d Two possible arrangements of a GSA in the face of the cube, E- and P-arrangements. In the E-arrangement, Me^③ (green) is located near the equator (left), whereas Me^③ is positioned around the pole in the P-arrangement (right). E and P stand for Equator and Pole, respectively e Two types of S₆-symmetric [2₆]¹²⁺ nanocubes, in which all six GSAs are located in E- or P-arrangement. f The geometry nets of possible configurational isomers except E- and P-[2₆]¹²⁺ shown in panel e. g Energy-minimized structure of [1₆]¹²⁺, in which one of six pairs of cation-π interactions working between blue and yellow aromatic rings is highlighted by a cyan rectangle. The colors of the segments of GSAs correspond to those of chemical structure of GSA 1²⁺ shown in Fig. 2a. h A geometry net of the nanocube assembled from C_2v-symmetric 1²⁺ to show the cation-π interactions in the triply stacked pyridinium-phenyl-pyridinium rings (broken lines).