Theoretical investigation of a new fulleren-like cluster C${}_{48}$ and a cubic diamond-like phase based on these clusters

With using the density functional theory method, the structure of a new carbon cluster C${}_{48}$, consisting of sp${}^2$-hybridized atoms, is studied. It is found that this cluster should be stable at 300 K. As a result of bulk compression of a simple cubic condensate of C${}_{48}$ clusters or endohedral Li@C${}_{48}$ clusters in the pressure range from 28 to 32 GPa, a cubic diamond-like phase can be formed. The structure of this cubic phase contains pores with a maximum diameter of 5.67 Å. The diamond-like phase must be stable up to 400 K. The results of the calculations show that this phase can be a wide-gap semiconductor with a band gap of 3.35 eV, a bulk modulus of 269.7 GPa, and a hardness of 54.6 GPa. For the experimental identification of the C${}_{48}$ clusters and the cubic diamond-like phase, X-ray powder diffraction patterns are simulated.