FIG. 8. Schematic diagram of slabs of coherent intergrowth between Pad and Cbs along the 15 Å repeat interpreted from the lattice images in Figs 3b and 4b. Such ‘structural modulators’ can be seen as long-period polysomes obtained in response to periodic chemical oscillations and local minima in free energy. The corresponding output signals realized by ordering of Pb in such polysomes are shown at the top of the figure in terms of 1 for the presence of 2Pb in D layer and 0 (gap) for the absence of Pb. These structural modulations are often thought of as being the result of long-range variation of strain in the lattice. Legend for layers: white = T; middle grey = D_Pad at the contact to Cbs; black = D; light grey = C.