Structures and electronic properties of C12Si8X8 (X = H, F, and Cl)

Abstract

The structural stabilities and electronic properties of C₁₂Si₈X₈ where X = H, F, and Cl are probed on the basis of density functional theory at the B3LYP/6-311++G**//B3LYP/6-31+G* level. Vibrational frequency calculations show that all the systems are true minima. The infrared spectra of the most stable C₁₂Si₈X₈ molecules are simulated to assist further experimental characterization. The functionalized structures and energy gaps between the highest occupied molecular orbital, HOMO, and the lowest unoccupied molecular orbital, LUMO, have been systematically investigated. It seems that C₁₂Si₈H₈ has more stability against electronic excitations via increasing the HOMO–LUMO gap comparing with C₁₂Si₈Cl₈ and C₁₂Si₈F₈. High charge transfer on the surfaces of our stable compounds, provokes further investigations on their possible application for hydrogen storage. The addition reaction energies of C₁₂Si₈X₈ are high exothermic, and C₁₂Si₈F₈ is more thermodynamically accessible.