The structural properties of LaRO3 (R=Cr, Mn, Fe): a first-principles calculation

National Conference on Theory of Magnetism

Li, Y.R.^1 ; Hou, Z.T.^1 ; Wang, T.X.^2 ; Li, Y.^1 ; Liu, H.Y.^1 ; Dai, X.F.^1 ; Liu, G.D.^1

School of Material Science and Engineering, Hebei University of Technology, Tianjin

300130, China^1

College of Physics and Information Engineering, Henan Normal University, Xinxiang

453007, China^2

关键词: A-type antiferromagnetic state;    Crystal parameters;    First principles method;    First-principles calculation;    Internal coordinates;    Lattice distortions;    Localized orbitals;    Magnetic ground state;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/827/1/012015/pdf
DOI  :  10.1088/1742-6596/827/1/012015

来源: IOP

【 摘 要 】

We investigate the structural properties of three lanthanum transition-metal oxides (LaRO3, R=Cr, Mn, Fe) by the first-principles method based on density functional theory. The crystal parameters and electronic structures are calculated for three different oxides. The results show that the magnitude of lattice distortion is the strongest in LaMnO3, and the slightest in LaCrO3among three compounds. The magnetic ground states of LaCrO3and LaFeO3are G-type antiferromagnet. However, for LaMnO3, GGA+U fails to predict the experimental ground state, and only the internal coordinates are relaxed and the experimental lattice constants are fixed, the LDA+U can reproduce the experimental A-type antiferromagnetic state. It is found that Fe-3d electrons in LaFeO3occupy the localized orbital with the low energy, while Cr-3d and Mn-3d electrons in LaCrO3and LaMnO3occupy the relatively wide energy states due to the strong hybridization between d electrons and p electrons of oxygen atoms.