Electronic and Crystalline Structure, Magnetic Response, and Optical Characterization of Rare-Earth Ruthenate Sr2HoRuO6

Sr₂HoRuO₆ ceramic has been synthesized and its structural, morphological, magnetic, optical, and electronic properties studied. Rietveld refinement of x-ray diffraction patterns revealed that this oxide material crystallizes in monoclinic perovskite structure in space group P2₁/n (no. 14). Scanning electron microscopy revealed polycrystalline surface morphology. x-Ray dispersive spectroscopy suggested that Sr₂HoRuO₆ was obtained with expected stoichiometry. Magnetic susceptibility curves as a function of temperature revealed ferrimagnetic feature of this material below the Néel temperature T_N of 14 K. Evidence of magnetic disorder was provided by the irreversibility observed in the zero-field-cooled and field-cooled responses of the susceptibility below T_irr = 169 K. Analysis of the diffuse reflectance spectrum suggested that this material behaves as a semiconductor with energy gap E_g of 1.38 eV. Results of band structure and density-of-states calculations are in agreement with the interpretation of Sr₂HoRuO₆ as a semiconductor. The ferrimagnetic behavior is interpreted as due to exchange mechanisms of d–f (Ru–O–Ho) electrons. The effective magnetic moment calculated from density functional theory was 93.5% of the experimental value obtained from Curie–Weiss fitting of the susceptibility curve.