Synthesis, Structure, and Magnetic Properties of SrLaMnSbO₆: A New B-Site Ordered Double Perovskite

The synthesis, structural characterization, and magnetic property studies of SrLaMnSbO 6 double perovskite oxide are reported. The crystal structure of SrLaMnSbO 6 has been solved by powder X-ray (PXD) and neutron diffraction (NPD) data in the monoclinic space group P 2 1 / n ( a = 5.6878(3) Å, b = 5.6990(2) Å, c = 8.0499(4) Å and β = 89.98(2)°; 295 K, NPD data). The Mn and Sb atoms are nearly completely ordered over the B -site of the perovskite structure. The octahedral framework displays significant tilting distortion according to the Glazer’s tilt system a − a − c + . X-ray absorption near-edge spectroscopic (XAS) studies show the presence of Mn 2+ and Sb 5+ formal oxidation states. The magnetic susceptibility data of SrLaMnSbO 6 indicate the presence of ferromagnetic correlations; the calculated effective paramagnetic moment, μ calcd = 5.92 μ B (for HS Mn 2+ (3d 5 ), S = 5/2; as evidenced by XAS data) is in good agreement with the value obtained experimentally (μ exp = 5.70 μ B ). Variable temperature neutron diffraction data show no evidence of structural transition down to 3.7 K. A long-range antiferromagnetic ordering is established at T N = 8 K as evidenced by the magnetic susceptibility and specific heat measurements. The magnetic structure at 3.7 K is characterized by k = 0 propagation vector and m 1 x = − m 2 x, m 1 y = m 2 y = 0, m 1 z = − m 2 z ( m x = 1.26(7) μ B, m z = 1.82(6) μ B ) coupling of magnetic moments on the Mn 1 (1/2,0,0) and Mn 2 (0,1/2,1/2) atoms with the ordered magnetic moment of 2.21(4) μ B .