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Context and Results: The structure, electronic and optical properties of single-layer transition metallic chalcogenides ZrX 3 (X = S, Se, Te) have been studied by density functional theory. The electron energy dispersion curve shows that ZrX 3 has semiconductor properties, in which the conduction band is mainly contributed by the correlated states of the Zr-d orbital, and the valence band is mainly contributed by the correlated states of the X-p orbital. It is found that b-axis and biaxial strain have great influence on the bandgap and the shift of density of states is also large. At the same time, the peak value of density of states increases greatly when biaxial strain is applied. It is of guiding significance for selecting suitable substrates to prepare two-dimensional ZrX 3 materials to study their electronic properties. The calculation of optical constants confirms that ZrX 3 has strong optical anisotropy. In the visible range, the light absorption efficiency of ZrX 3 in the direction of electric field polarization [100] is higher than that in the direction of [010]. The reflectance spectral results show that ZrS 3 and ZrSe 3 in the [100] directions have the highest reflectance, and ZrTe 3 in the [010] direction has the highest reflectance, even in the long electromagnetic radiation range (up to 10 eV), which is of great significance for the construction of visible optical devices., Computational Method: All computations have been carried out based on density functional theory (DFT) as implemented in the CASTEP code. The pseudo-potential is adopted by the norm conserving, and the exchange correlation functional is adopted by the Perdew-Burke-Ernzerhof in local generalized gradient approximation (GGA)., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Context: Based on first principles, the structure, elasticity, mechanics, electronics, and optical properties of cubic K 2 Pb 2 O 3 were studied. The structural parameters calculated by this method are close to the previous theoretical results. The elastic constant, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and mechanical stability are studied, and it is shown that cubic K 2 Pb 2 O 3 is mechanically stable, isotropic, and brittleness. The electrical conductivity and chemical bonding of cubic K 2 Pb 2 O 3 were analyzed based on the calculated band structure, density of states (DOS), and bond populations. The dispersion of optical functions, including the dielectric function, refractive index, extinction coefficient, reflectivity, absorption coefficient, and loss function, is displayed and analyzed., Methods: All computations have been carried out based on density functional theory (DFT) as implemented in the CASTEP code. The norm conservation pseudopotential method is used to exchange correlation functionals within the generalized gradient approximation (GGA)., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Context: Based on the first-principles calculations, this paper investigates the structural, elastic, electronic, and optical properties of albite and kaolinite, respectively. It is determined that both of them show structural stability, mechanical stability, and brittleness by calculating formation enthalpy, phonon dispersion, elastic, and mechanically relevant properties. Both materials are insulators with an indirect bandgap. By calculating the TDOS and PDOS, the main characteristics of the electronic structure of NaAlSi 3 O 8 come from O-2p and Si-3p states, O-2p, and Al-3p states hybridization, similar to Al 4 [Si 4 O 10 ](OH) 8 . The covalence of Si-O bonds in NaAlSi 3 O 8 is greater than Al-O bonds, and the covalent property sequence of Si-O bands in NaAlSi 3 O 8 is Si2-O3 > Si1-O4 > Si2-O2 > Si1-O8 > Si1-O6 > Si3-O2 > Si3-O4. The optical anisotropy of NaAlSi 3 O 8 and Al 4 [Si 4 O 10 ](OH) 8 is analyzed., Methods: First-principles density functional theory (DFT) calculation was carried out by the CASTEP computer program. The GGA-PW91 exchange-correlation was used. The energy convergence tolerance, the maximum force, and the maximum displacement were set in the calculation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)