Alemi, Abdolali, et al. International nano letters 3 (2013): 1-11.
The UV-visible and photoluminescence spectra of hydrothermally synthesized crystalline lithium metasilicate (Li2SiO3) and lithium disilicate (Li2Si2O5) nanomaterials were studied. The band intensity in the emission spectra of both compounds increased with increasing reaction time. The electronic band structure and density of states calculated by density functional theory (DFT) method showed that the indirect band gaps of Li2SiO3 and Li2Si2O5 were 4.575 and 4.776 eV, respectively. The optical properties of the compounds, including dielectric, absorption, reflectivity, and energy loss spectra, were calculated by DFT method and analyzed according to the electronic structure.
The electronic band structure as well as the density of states (DOS) of the compounds were calculated by density functional theory (DFT) using one of three nonlocal gradient corrected exchange-correlation functionals. The calculations were performed using the CASTEP code, which uses a plane wave basis set for valence electrons and a norm-conserving pseudopotential for core electrons. The number of plane waves included in the basis was determined by a cutoff energy Ec of 500.0 eV. The summation of the Brillouin zones was performed by k-point sampling using a Monkhorst-Pack mesh with parameters of 5 × 5 × 5 for Li2SiO3 and 4 × 5 × 2 for Li2Si2O5. Pseudo-atomistic calculations were performed for Li-2s2, Si-3s2 3p2, and O-2s2 2p4. The parameters and convergence criteria used in the calculations were set by the default values of the CASTEP code, e.g., reciprocal space pseudopotential representation, intrinsic energy convergence tolerance of 1×10eV, Gaussian smearing scheme with a smear width of 0.1 eV, and Fermi energy convergence tolerance of 1×10eV.
Soares, Viviane O., et al. Ceramics International 47.2 (2021): 2793-2801.
