Structural, Electronic, and Optical Properties of Photoluminescence Materials: Zn ₃ X ₂ O ₈ (X = P, V)

This present study offers a comprehensive understanding of the structural, vibrational, elastic, electronic, and optical properties of zinc‐based ternary oxides Zn 3 X 2 O 8 (X = P, V) using density functional theory (DFT) calculations. Zn 3 P 2 O 8 and Zn 3 V 2 O 8 crystallize in monoclinic and orthorhombic structures, respectively. The phonon density of states indicates that oxygen, along with both cations (Zn, X), actively participate in the low‐frequency vibrational modes. Conversely, X and O atoms primarily contribute to the higher and mid‐phonon frequencies. A blue shift in the computed frequencies was observed upon transitioning from X = P → V atom. The dynamical and mechanical stability of Zn 3 X 2 O 8 was established through the evaluation of phonon dispersion relations and elastic constants. The Elastic constants and the Bulk modulus (B) suggest that Zn 3 P 2 O 8 (B = 89.77 GPa) is more compressible than Zn 3 V 2 O 8 (B = 130.21 GPa) and both compounds exhibit sensitivity to shear forces. Poisson's and Pugh's ratios confirm the predominant ionic bonding and ductile nature of these compounds. The electronic band structure, calculated using the HSE06 hybrid functional for improved accuracy, shows that the conduction band minima are primarily composed of Zn‐ s states, with a smaller contribution from p states. Meanwhile, the valence band maxima are predominantly derived from oxygen p states, which play a key role in the electronic transitions. Calculated electronic and optical properties suggest that the studied compounds may be suitable for photoluminescence applications.