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The exploration of perovskite compounds incorporating actinide and divalent elements reveals remarkable characteristics. Focusing on PbBkO3, RaBkO3, and SrBkO3, these materials were studied using density functional theory (DFT) via the CASTEP code to analyze their electronic, optical, and mechanical properties. The results show semiconductor behavior, with respective band gaps of 1.320 eV for PbBkO3, 3.415 eV for RaBkO3, and 2.775 eV for SrBkO3. Additionally, the elastic constants Cij, bulk modulus B, elasticity modulus G, Young's modulus Y, and Poisson's ratio v were optimized, highlighting anisotropic behavior. The mechanical stability of the compounds meets Born's criteria, and RaBkO3 stands out with a stable lattice dynamic, as demonstrated by phonon dispersion curves in the Pm-3 m space group. The optical properties of these materials indicate they are excellent absorbers of incident radiation, suggesting their potential for applications in magnetic sensors due to their anisotropic magnetic behavior, as well as for capturing solar radiation in the ultraviolet range. [ABSTRACT FROM AUTHOR]

Herein, a series of perovskite‐type hydride materials RMnH3 (R = Ca, Sr, and Ba) are investigated by density functional theory for solid‐state hydrogen storage. Their structural, mechanical, electronic, and optical properties are calculated and their thermodynamic, dynamic, and mechanical stability is assessed. All compounds crystallize in the undistorted cubic perovskite system with the Pm‐3m symmetry. The results from mechanical properties, based on parameters such as Poisson's ratio (ν) and the G/B ratio, indicate that CaMnH3 and SrMnH3 exhibit brittle behavior, primarily attributed to the dominance of ionic bonds, while BaMnH3 is distinguished by its ductility, resulting from a prevalence of covalent bonds. Additionally, the electronic structure analysis reveals that all examined hydrides possess metallic behavior. Further calculations of the optical properties are also performed, providing supplementary insights into the physical features of the hydrides. The gravimetric hydrogen storage capacities (Cwt%) are calculated, with values of 2.96 wt% for CaMnH3, 2.019 wt% for SrMnH3, and 1.513 wt% for BaMnH3, accompanied by respective desorption temperatures of 214.83, 193.42, and 145.43 K. Overall, these results highlight the potential of perovskite hydrides RMnH3 as promising materials for hydrogen storage applications, significantly contributing to a sustainable energy future. [ABSTRACT FROM AUTHOR]