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First-principles density functional theory calculations were performed to assess the pressure effect on structural, electronic, mechanical, thermal, and optical properties of cubic intermetallic UIr3. The calculated lattice parameter deviates from the experimental value by 0.40%, indicating the reliability of the present study. The obtained lattice constant decreases at a constant rate with pressure over the entire pressure range. The band structure and Fermi surface disclose the metallic nature of UIr3. The external pressure suppresses the overlapping between the valence and conduction bands and reduces the total density of state at the Fermi level. The pseudogap moves to the left from the Fermi level with increasing pressure, which indicates a decrease in the structural stability of UIr3. Peaks in the valence band move toward deeper energy positions when the external pressure is increased from 0 to 25 GPa, indicating the increase in the covalency of UIr3. Contour maps of charge density and Mulliken population analysis imply that UIr3 has also partial ionic and covalent nature in chemical bonding. In the considered pressure range, UIr3 maintains its mechanical and dynamical stability as well as ductility and machinability. The elastic anisotropic level of UIr3 increases slightly with fluctuations above the pressure of 5 GPa. Shape change in UIr3 will be more difficult due to the increase in shear modulus and microhardness under the external pressure. Thermal properties of UIr3 are favorable for being a promising thermal barrier coating material, and optical reflectivity makes it a potential candidate material for coating to diminish solar heating.

The structural, optical, electrical, thermodynamic, superconducting, and mechanical characteristics of LiGa 2 Ir full-Heusler alloys with the MnCu 2 Al configuration were comprehensively examined in this work using the first-principles computation approach premised upon density functional analysis. This theoretical approach is the first to investigate the influence of pressure on the mechanical and optical characteristics of LiGa 2 Ir. The structural and chemical bonding analysis shows that hydrostatic pressure caused a decrease in the lattice constant, volume, and bond length of each cell. According to the mechanical property calculations, the LiGa 2 Ir cubic Heusler alloy exhibits mechanical stability. It also has ductility and anisotropic behavior. This metallic substance shows no band gap throughout the applied pressure range. The physical characteristics of the LiGa 2 Ir full-Heusler alloy are analyzed in the operating pressure range of 0−10 GPa. The quasi-harmonic Debye model is employed to analyze thermodynamic properties. The Debye temperature (291.31 K at 0 Pa) increases with hydrostatic pressure. A newly invented structure attracted a lot of attention around the globe for its superior superconductivity (T c ∼ 2.95 K). Optical functions have also been improved after applying stress to utilize it in optoelectronic/ nanoelectric devices. The optical function analysis is supported strongly by the electronic properties. Due to these reasons, LiGa 2 Ir imposed an essential guiding principle for relevant future research and could be a credible candidate substance for industrial settings.

The study discusses the pressure-induced behavior of structural and optical properties of rare earth metal cubic perovskite SrPuO3. The lattice parameter is found 4.33 Å, which agrees with other studies and the bulk modulus of the structure is 157.989 GPa. First-principle computation shows that the value of dielectric constants falls drastically in the visible range. With increasing pressure, there is a significant increase in absorption and conductivity of the material. These increases occur inside the visible range, promoting the material to be used as optoelectronic devices. Reflectivity and refractive index under pressure is found to be high for the red light and low for the violet zone. Again, these start to increase for additional frequencies. The frequency-dependent loss function is also described in work.

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