Figure 2. Analysis of nanocrystal superlattices in using SEM and using SAXS.

(a–d) Rhombic dodecahedra form a face-centered cubic superlattice visible along different projection directions. (e–h) Octahedra are found predominantly in two crystallographically distinct superlattices: simple hexagonal, s.h., (e–g) and monoclinic (e,h). (i,j) Cubes assemble into a simple cubic lattice. (k) A macroscopic view shows a complete superlattice film. (l–p) Two-dimensional and (q–u) radially averaged SAXS images of assembly products exhibit clear diffraction spots and peaks, respectively, highlighting long-range order in superlattices of sRD (l,q), mRD (m,r), lRD (n,s), octahedra (o,t) and cubes (p,u). For (l–p) the data are shown in data on a logarithmic intensity scale and for (q–u), the vertical axes represent the logarithmic intensity. Peaks are not indexed for the octahedron superlattice (o,t), because the crystal structure is not unique. See Supplementary Movie 1 for more information. Scale bars, (i) 200 nm; (k) 10 μm; all others are 100 nm.