An Examination from Fundamental Principles Regarding the Structural, Elastic, Electronic, Magnetic, and Optical Characteristics of F Based Oxide full-Heusler Compounds

This study presents a comprehensive investigation of the structural, electronic, magnetic, elastic, and optical properties of full‑Heusler compounds O₂XF (X = Ca, Sr, Ba) using first‑principles calculations based on density functional theory (DFT). The computations were carried out using the full‑potential linearized augmented plane wave (FP‑LAPW) method implemented in WIEN2k. The exchange–correlation potential was described using the generalized gradient approximation (GGA‑PBE), while the Tran–Blaha modified Becke–Johnson (TB‑mBJ) potential was applied to obtain accurate electronic structures. All compounds are found to crystallize in the Hg₂CuTi‑type structure with a ferromagnetic ground state. Elastic constants calculated via the IRelast module confirm their mechanical stability and ductile nature. Band structure and density of states (DOS) analyses reveal half‑metallic behavior: the majority‑spin channel exhibits a semiconducting character, whereas the minority‑spin channel remains metallic. The total magnetic moment of 3 μB per formula unit for all compounds agrees well with the Slater–Pauling rule Mtot=(24−Ztot) μB. Overall, the O₂XF (X = Ca, Sr, Ba) full‑Heusler alloys are identified as mechanically robust half‑metallic ferromagnets with 100% spin polarization, making them strong candidates for future spintronic and sustainable energy applications.