Generalizing the Chiral Self-Assembly of Spheres and Tetrahedra to Non-Spherical and Polydisperse Molecules in (C70)x(C60)(1-x)(SnI4)2

Abstract

We describe the spontaneous chiral self-assembly of C<sub>70</sub> with SnI<sub>4</sub> as well as a mixture of C<sub>60</sub> and C<sub>70</sub> with SnI<sub>4</sub>. Macroscopic single crystals with the formula (C<sub>70</sub>)<sub>x</sub>(C<sub>60</sub>)<sub>1-x</sub>(SnI<sub>4</sub>)<sub>2</sub> (x = 0-1) are reported. C<sub>60</sub>, which is spherical, and C<sub>70</sub>, which is ellipsoidal, form a solid solution in these crystals, and the cubic lattice parameter of the chiral phase linearly increases as x grows from 0 to 1 in accordance with Vegard’s law. Our results demonstrate that nonspherical particles and polydispersity are not an impediment to the growth of chiral crystals from high-symmetry achiral precursors, providing a route to assemble achiral particles including colloidal nanocrystals and engineered nanostructures into chiral materials without the need to use external templates.<br>