Ab initio calculations of some electronic and vibrational properties of molecules based on multi-layered stacks of cyclic C _6

摘要

The vibrational and electronic properties of a class of novel carbon molecules constructed from stacked layers based on cyclic C ~6 components have been studied using first principles density functional techniques. Data are presented for tubular stacked cyclic C _6 molecules (C _6) _n with 2 n 16. Infrared and Raman spectra have been calculated for all molecules. We find that a number of low energy infrared and Raman modes have energies that are strongly correlated with the overall length of the (C _6) _n structure, but the energy of the radial breathing mode is identical to that predicted for a single-walled carbon nanotube with a diameter of 0.295 nm. The HOMO-LUMO energy gap and the ionization energy approach 2.28±0.02 eV and 6.8±0.3 eV, respectively, in longer molecules. (C _6) _n molecules are found to have high stability and may be promising candidates for nanoelectronic applications.