A theoretical investigation on the structural and electronic properties with the effective mass of the nickel-based perovskites

Abstract

In the realm of electronic materials, the effective mass of electrons serves as a crucial parameter that intimately characterizes their electronic properties. In this investigation, we have conducted a meticulous evaluation of the effective mass of electrons in a diverse array of pure Nickel-based perovskites, including LaNiO3, La0.8Ca0.2NiO3, La0.5Ca0.5NiO3, La0.2Ca0.8NiO3, La4Ni3O10, La3Ni2O7, and La2NiO4. Our cutting-edge methodology is rooted in the first-principles calculations based on density functional theory (DFT). In essence, we performed a detailed analysis of the density of states (DOS) and the band structure of all the materials, yielding results that exhibit superb congruity with theoretical and experimental data. We then proceeded to estimate the effective mass of electrons by scrutinizing the curvature of the electronic conduction band via the parabolic fit approximation around the extremum of the band (i.e., Γ-point). The effective mass of the LaNiO3, La0.8Ca0.2NiO3, La0.5Ca0.5NiO3, La0.2Ca0.8NiO3, La4Ni3O10, La3Ni2O7, and La2NiO4 has been calculated to be -0.4001 me, -0.4327 me, -0.5000, 0.6190, 0.6447, -4.5480, and -8.7852 respectively along the direction L-Γ-S path in the reciprocal space. The outcome of our trailblazing study is that the effective masses manifest a remarkably high correlation with the energies of the conduction band extremum (i.e., LUMO) and DOS around the Fermi energy level. Intriguingly, our observations also indicate that the introduction of the Ca atom as a substitution dopant of the La atom in LaNiO3 leads to a significant change in the effective mass of the electron, a phenomenon that can be elucidated by the distinctive properties of the A- and B-sites in the perovskite structure.