Electronic structure of crystal-forming fullerenes C 2 n , fulsicenes Si n C n , and their crystals—Fulsicenites

A number of crystal-forming polyhedral clusters X n Y n from which zeolite-like covalent crystals can be constructed and synthesized through copolymerization by faces are proposed. A series of the smallest sized crystal-forming carbon clusters C 2 n (where n = 10, 12, 14, 16, 18, 24, 36, 60) and silicon carbide clusters Si n C n (where n = 12, 16, 18, 24, 36, 60) are constructed. Their optimized geometries, electronic structures, charge transfers, band gaps, cohesive energies, and electron density maps are calculated using the spinrestricted Hartree-Fock method in the 6–31 G ( d ) basis set. The Si 12 C 12 and Si 24 C 24 clusters, referred to as the fulsicenes, are used to construct possible crystals with rock salt (Si 12 C 12 ), simple cubic (Si 24 C 24 ), body-centered cubic (Si 12 C 12 ), face-centered cubic (Si 24 C 24 ), and hyperdiamond (Si 12 C 12 ) lattices, which are termed fulsicenites. Their X-ray diffraction patterns are calculated.