High Resolution Image Download MS PowerPoint Slide For the first time, the concept of supramolecular synthons was applied to giant rigid superspheres based on pentaphosphaferrocene [Cp R Fe(η 5 -P 5 )] (R = Me, Et) and Cu(I) halides, which reach 2.1–3.0 nm in diameter. Two supramolecular synthons, σ–π and π–π, are discovered based on halogen···Cp R and Cp*···Cp* specific interactions, respectively. The geometry of the synthons is reproducible in a series of crystal structures of various supramolecules. The σ–π synthon alone is realized more frequently for Br-containing superspheres. A combination of the σ–π and π–π synthons is more typical for Cl-containing supramolecules. Each supramolecule can bear up to nine synthons to give mostly 2D and 3D architectures.