Structural, mechanical and optical properties of lead-free ferromagnetic Ca2MnMoO6 double perovskite for advanced optoelectronic applications

In this study, we systematically investigate the structural, electronic, mechanical and optical properties of the double perovskite oxide Ca₂MnMoO₆ using first principles calculations. The material crystallizes in a stable cubic phase with space group Fm3m. The obtained lattice constants are found to be 8.48 Å. The dynamic and thermodynamic stability are confirmed by phonon dispersion curve and molecular dynamic simulation. Magnetic ground state analysis reveals that the ferromagnetic (FM) configuration is energetically favorable over antiferromagnetic (AFM) configuration (AFM). Electronic band structure analysis indicate that material have half metallic behavior. In spin up case the material has band gap of 1.3 eV while in spin down case it is metallic. Furthermore, elastic constants are computed to ensure the mechanical stability and found that it is mechanically stable. Optical analysis reveals that high static dielectric constant and strong absorption in the visible to ultraviolet region. Furthermore, the reflectivity reaches up to 77 % around 8.9 eV, highlighting potential for UV reflective applications. These findings suggest that Ca₂MnMoO₆ is a promising candidate for spintronic and optoelectronic device applications.