NANO LETTERS, vol.18, no.8, pp.5257-5261, 2018 (SCI-Expanded)
The shape of individual building blocks is an important parameter in bottom-up self-assembly of nanostructured materials. A simple shape change from sphere to spheroid can significantly affect the assembly process due to the modification to the orientational degrees of freedom. When a layer of spheres is placed upon a layer of spheroids, the strain at the interface can be minimized by the spheroid taking a special orientation. C-70 fullerenes represent the smallest spheroids, and their interaction with a sphere-like C-g0 is investigated. We find that the orientation of the C-70 within a close-packed C-70 layer can be steered by contacting a layer of C-60. This orientational steering phenomenon is potentially useful for epitaxial growth of multilayer van der Waals molecular heterostructures.