Figure 6.

Dimensions and orientation of the parallelepiped representing one plate of a GSE formed by layers of seven platelets. (A) Positions and numbering of the eight vertices of the parallelepiped in the $\mathit{xyz}$ reference system, $z$ being the axis of the GSE. The $x,y,z$ coordinates of the vertex 1 are $R$,0,$z_1$. The parallelepiped angles ${\alpha }_P$, ${\beta }_P$ and ${\gamma }_P$ are represented by the magenta, the orange and the green arcs, respectively. The basis of the parallelepiped, defined by the vertices 1, 5, 3 and 7, is placed on the same plane of to the circle represented in red. $\beta$ is the angle between the $z$ axis and the diagonal of the basis parallelogram. $\alpha$ is the angle that defines the widening of the truncated cone representing the inner cavity of the GSE. (B) Representation of the parallelepiped shown in panel A according to the low-density and high-density (red and dark-red volumes, respectively) starch. $\varphi$ is the low-to-high density volume fraction and corresponds to the ratio along the $c$ axis, as shown. (C) Top view of a layer of seven parallelepipeds that share the same distance $R$ of their vertex 1 from the z-axis. (D) Specular image of the parallelepiped shown in panel A across the $\mathit{xz}$ plane. Vertices 6, 8, 5 and 7 have been renumbered. (E) Specular representation across the $\mathit{xz}$. plane of the parallelepiped shown in panel D. (F) Top view of seven specular parallelepipeds displaced as described for panel D.