Magnetic and optical properties in the 1D TM–O chain compounds Sr2TMO3 (TM = Ni, Co): A first-principle investigation

Abstract

In this paper, we have calculated the structural, electronic, magnetic and optical properties of Sr2NiO3 and Sr2CoO3 using density functional theory (DFT) within generalized gradient approximation (GGA). The crystal structure of both materials is well described with Immm (No. 71) symmetry which are isostructural with Sr2CuO3 and both are quasi-one-dimensional (1D) rectangular lattice G-type antiferromagnets, in consistent with the experimental data. Due to a distortion, Sr2CoO3 lifts the near-degeneracy [Formula: see text] and [Formula: see text] states of the local Co electronic configuration, which demonstrates a strong coupling between the structural lattice and the electronic configuration. The calculated band structure shows a band gap of 1.376 eV for Sr2NiO3 and a band gap of 1.735 eV for Sr2CoO3. Ni and Co ions are in the high-spin [Formula: see text] and [Formula: see text] configurations with the magnetic moments of 1.585 [Formula: see text] and 2.587 [Formula: see text], respectively. Based on the Heisenberg Hamiltonian model, we conclude that the superexchange intrachain TM–O–TM superexchange interaction is predominant and interaction between the 1D chains is weak. According to the calculated dielectric function, absorption spectrum and electron energy loss spectrum, the optical responses suggest that Sr2NiO3 shows the unique anisotropic structure and interaction of the application in optoelectronics.