First-principles study of LaCrO₃ and LaCoO₃ perovskites for thermo-spintronics: Structural, electronic, and thermal comparison with LaMnO₃ and LaFeO₃

In this study, we employed first-principles calculations within the framework of density functional theory to analyse the structural, electronic, mechanical and thermal properties of LaCrO₃ and LaCoO₃, benchmarking them against the reference compounds LaMnO₃ and LaFeO₃. The results reveal that both perovskites are dynamically stable with negative formation energies, although their lattice parameters differ slightly owing to magnetic effects. Electronically, LaCrO₃ displays half-metallic behaviour, whereas LaCoO₃ is semiconducting, a distinction rooted in d–p orbital hybridisation. Both compounds satisfy Born’s mechanical stability criteria and exhibit ductile characteristics, while thermal analyses confirm enhanced performance under high pressures. Beyond these baseline results, the present work uncovers several previously unreported behaviours under mechanical stress. LaCrO₃ retains its spin-polarised half-metallicity under tensile strains up to 4 %, whereas LaCoO₃ undergoes a pressure-induced symmetry breaking near a 3 % volume compression. Moreover, a marked lattice stiffening is observed, with the Debye temperature rising by more than 35 % at elevated pressures. These discoveries point to robust electronic and thermodynamic responses and provide fresh design guidelines for durable spintronic and thermoelectric devices. Consequently, the combined insights confirm the promise of LaCrO₃ and LaCoO₃ for thermo-spin-tronic applications and pressure-resistant coatings, while preserving the original research methodology and analytical toolkit.