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Abstract: The band structure and optical properties of 3C–SiC are studied by using a full potential linearized augmented plane waves (FPLAPW) method. The imaginary and real parts of the dielectric function have been obtained from the band structure calculation. The critical point structure of the dielectric function is analyzed to identify the optical transition. The refractive index, extinction coefficient and reflectivity have been calculated from obtained dielectric function. The calculated results are in agreement with the experiments. [Copyright &y& Elsevier]

We study the electronic and optical properties of hexagonal 6H–SiC crystal, using ab initio full potential augmented plane wave method. The density of states (DOS) and band structure are presented based on local density function theory. From the electronic structure calculation, the imaginary part of the dielectric function has been obtained directly using the joint DOS and the optical matrix elements. With band gap correction, the real part of dielectric function can be derived from the imaginary part by the Kramers–Kronig relationship. The reflectivity for normal incidence is also calculated. The resulting spectrum is in good agreement with available experimental data in a wide energy range. [Copyright &y& Elsevier]

Presents a theoretical calculation of the atomic and electronic structure of beta-silicon carbide and its non-polar surface using the full potential linear augmented plane wave approach. Agreement of the calculated lattice constant and bulk modules with experimental data; Calculation of the atomic and electronic structure of silicon carbide using the slab and supercell model.

PL band of 340 nm has been observed from sol–gel silica with and without the addition of nano-sized SiC/C powder. With the increasing of annealing temperature, the intensity of the 340-nm PL band in pure silica decreases remarkably, while that in SiC/C powder-added silica is enhanced. Based on the Fourier-transform infrared (FTIR) absorption and X-ray photoelectron spectroscopy (XPS) spectra, the authors suggest that the addition of nano-sized SiC/C powder into porous silica (PSO) will strengthen the silica network and prevent it from shrinking during heat treatment. By this mechanism, the 340-nm PL band is stabilized by the presence of SiC/C powder. [Copyright &y& Elsevier]