Spin reorientation in antiferromagnetic Dy₂FeCoO₆ double perovskite

We explored the electronic and magnetic properties of the lanthanide double perovskite Dy₂FeCoO₆ by combining magnetization, Raman and Mössbauer spectroscopy and neutron diffraction along with density functional theory (DFT) calculations. Our magnetization measurements revealed two magnetic phase transitions in Dy₂FeCoO₆. First, a paramagnetic to antiferromagnetic transition at T _N = 248 K and subsequently, a spin reorientation transition at T _SR = 86 K. In addition, a field-induced magnetic phase transition with a critical field of H _c ≈ 20 kOe is seen at 2 K. Neutron diffraction data suggested cation-disordered orthorhombic structure for Dy₂FeCoO₆ in Pnma space group which is supported by Raman scattering results. The magnetic structures ascertained through representational analysis indicate that at T _N, a paramagnetic state is transformed to Γ₅(Cx, Fy, Az) antiferromagnetic structure while, at T _SR, Fe/Co moments undergo a spin reorientation to Γ₃(Gx, Ay, Fz). The refined magnetic moment of (Fe/Co) is 1.47(4) μ _B at 7 K. The antiferromagnetic structure found experimentally is supported through the DFT calculations which predict an insulating electronic state in Dy₂FeCoO₆.