Platonic Hexahedron Composed of Six Organic Faces with an Inscribed Au Cluster

The structures of nanomaterials determine their individual
properties
and the suprastructures they can form. Introducing anisotropic shapes
and/or interaction sites to isotropic nanoparticles has been proposed
to extend the functionality and possible suprastructure motifs. Because
of symmetric anisotropy, Platonic solids with regular polygon faces
are one of the most promising nanoscale structures. Introduction of
Platonic solid anisotropy to isotropic nanomaterials would expand
the functionality and range of possible suprastructure motifs. Here,
we demonstrate a novel strategy to obtain nano-Platonic solids through
the face coordination of square porphyrins on an inscribed Au sphere
with adequate size. The face coordination of the multidentate porphyrin
derivatives, with four acetylthio groups facing the same direction,
on the Au cluster encased the Au cluster in a Platonic hexahedron
with six porphyrin faces. Transmission electron microscopy, mass spectrometry,
elemental analysis, and scanning tunnelling microscopy were used to
confirm the formation of the nano-Platonic hexahedron.