A lens-shaped supramolecule based on the bulky pentaphosphaferrocene [Cp BIG Fe(η 5 -P 5 )] and CuBr 2 .

Besides inherent fullerene-like hollow spheres, the metallasupramolecular chemistry of pentaphosphaferrocenes and CuBr 2 afforded a conceptually new product, a compact 3.2 nm sized supramolecule [{1d} 6 (CuBr) 32 (CH 3 CN) 6 ] formed by six largest pentaphosphaferrocene units [Cp BIG Fe(η 5 -P 5 )] (1d: Cp BIG = η 5 -C 5 (4- n BuC 6 H 4 ) 5 ) so far and a framework of 32 copper and 32 bromide ions.