High-pressure and high-temperature synthesis of a novel perovskite compound: Magnetic and electric properties of the rhodium oxide SrRhO3

Novel perovskite compound SrRhO3 was synthesized in a polycrystalline form by high-pressure technique at 6 GPa and 1500 °C, followed by measurements of magnetic susceptibility, electrical resistivity, thermopower, and specific heat. Powder x-ray diffraction study found the slightly distorted perovskite structure, GdFeO3-type, to be likely to SrRhO3; space group was Pnma and lattice parameters were a = 5.5394(2) Å, b = 7.8539 (3) Å, and c = 5.5666(2) Å. Oxygen vacancies in the perovskite were quantitatively investigated by thermogravimetric analysis and then found either absent or at least insignificant. The title compound shows a Fermi-liquid behavior in its electrical resistivity. The magnetic susceptibility is large [ Χ(300) ∼ 1.1 × 10-3 emu/mol-Rh], and the characteristics seem to be intermediate between enhanced Pauli- and Curie-Weiss-type paramagnetism