Fig. 4

Assembled structures of monolayer films constructed from ionic pillar[5]− and pillar[6]arenes. FM-AFM images of a 1[5]L and f 1[6]L Scale bar, 10 nm. d, i Fourier transform (FFT) spectra of FM-AFM images of a 1[5]L and f 1[6]L, respectively. Scale bar, 0.5 nm⁻¹. b, g Enlarged FM-AFM images of a 1[5]L and f 1[6]L, respectively. The blue features shown in (b) indicate that the hexagonal voids displayed high regularity and directionality over a long range. In contrast, in (g), the direction of the hexagonal packing (the yellow ring) pattern indicated by blue line was different from that of another hexagonal packing pattern indicated by red line. c Snapshot of a portion of a 1000-molecule 1[5]L system with a packing fraction η of 0.224 and e the corresponding FFT image. h Snapshot of a portion of the 1000-molecule 1[6]L system with η = 0.294, and j the corresponding FFT image