Comprehensive First‐Principles Investigation of β‐Ca₅Si₂N₆: Structural, Mechanical, Electronic, Optical, and Catalytic Insights

Herein, the findings of a thorough theoretical investigation of the structural, mechanical, electronic, optical, and catalytic properties of β‐Ca 5 Si 2 N 6 are presented using the pseudopotential plane‐wave method based on density functional theory. This nitridosilicate compound has a mechanically stable monoclinic lattice. Along the principal axes, it has high directional compressive and tensile strength. The isotropic compressive strength is moderate, and the shear deformation resistance is low. It also has a moderate Vickers hardness, a low minimum thermal conductivity, and a high Debye temperature. It has been found that β‐Ca 5 Si 2 N 6 is a semiconductor with a wide direct energy bandgap of 3.752 eV and a mix of covalent and ionic bonds. It can strongly absorb UV light (up to 2.7 × 10 5 cm − 1 ), reflect light less than 35%, lose very little energy (<4%), has a maximum refractive index of 2.9, and exhibits a peak photoconductivity of 5.602 fs − 1 . These properties make it a suitable choice for optical coatings and photonic devices. With band‐edge potentials of −1.498 and 2.253 eV, the material also has good catalytic activity, which means it works well for photocatalytic water splitting and organic pollutant decomposition. β‐Ca 5 Si 2 N 6 shows significant potential for advanced applications in optoelectronics, catalysis, and other high‐tech fields.