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Updated: Aug 6, 2026
Effect of Microwave Synthesis Conditions on the Structure of Nickel Hydroxide Nanosheets
Published on: August 18, 2023
Electronic and Magnetic Properties of Nickel Oxychlorides with Tetragonal Crystal Structures
Yaoyao Hao1, Yixuan Du1, Huamei Zhang1
1Key Laboratory of Applied Chemistry, Yanshan University, Qinhuangdao066004, P. R. China.
Abstract:
The discovery of pressure-induced superconductivity in Ruddlesden-Popper nickelates has motivated the search for ambient-pressure tetragonal superconductors. Using first-principles calculations, we investigate the electronic and magnetic properties of three-layered nickel oxychlorides: Sr2NiO3Cl, Sr3Ni2O5Cl2, and the hypothetical reduced phase Sr3Ni2O4Cl2. In agreement with the previous studies, although ferromagnetic interactions predominate in Sr2NiO3Cl, the underlying mechanism is governed by the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction rather than superexchange, which is attributed to the coexistence of localized 3dz2 moments and the itinerant 3dx2-y2-derived carriers. In Sr3Ni2O5Cl2, the dominant RKKY interaction within the bilayer perovskite blocks combined with strong antiferromagnetic (AFM) superexchange coupling along the c axis yields A-type AFM ordering. Furthermore, the uniform Ni3+ oxidation state and pronounced buckling of the NiO2 basal plane distinguish it from high-pressure superconductor La3Ni2O7, which might be one reason potentially contributing to the absence of superconductivity. Removal of the inner-apical oxygen from the precursor Sr3Ni2O5Cl2 to form Sr3Ni2O4Cl2 not only converts the Ni oxidation state but also profoundly alters the electronic and magnetic properties, inducing G-type AFM ordering and insulating behavior. Collectively, these results reveal profound tunability of the electronic and magnetic properties in layered nickel oxychlorides and may offer valuable insights for designing ambient-pressure tetragonal new Ni-based potential superconductors.
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