Synthesis and X-ray diffraction study of nanostructured particles of cuprate manganites LaM 2 II CuMnO6 (MII = Mg,Ca, Sr,Ba)

Cuprate manganites of the composition LaM ₂ ^II CuMnO₆ (M^II = Mg, Ca, Sr, Ba) were synthesized from lanthanum, copper(II), and manganese(III) oxides and alkaline-earth metal carbonates by high-temperature solid-phase synthesis. By grinding the produced substances in a ball mill, their nanostructured particles were obtained, the sizes of which were determined with an electron microscope. Indexing the X-ray powder diffraction patterns of the cuprate manganites established that all of them crystallize in the cubic system with the following unit cell parameters: LaMg₂CuMnO₆: a = 15.523 ± 0.033 Å, Z = 6, V ⁰ = 3740.48 ± 0.10 ų, V _el.cell ⁰ = 623.41 ± 0.03ų, ρ_X-ray = 5.81 g/cm³, and ρ_pycn = 5.75 ± 0.06 g/cm³; LaCa₂CuMnO₆: a = 15.422 ± 0.058 Å, Z = 4, V ⁰ = 3667.94 ± 0.174 ų, V _el.cell ⁰ = 916.48 ± 0.04 ų, ρ_X-ray = 3.77 g/cm³, and ρ_pycn = 3.72 ± 0.05 g/cm³; LaSr₂CuMnO₆: a = 15.275 ± 0.049 Å, Z = 4, V ⁰ = 3564.05 ± 0.27 ų, V _el.cell ⁰ = 891.01 ± 0.07 ų, ρ_X-ray = 4.31 g/cm³, and ρ_pycn = 4.25 ± 0.05 g/cm³; and LaBa₂CuMnO₆: a = 15.589 ± 0.029 Å, Z = 4, V ⁰ = 3788.39 ± 0.09 ų, V _el.cell ⁰ = 947.10 ± 0.02 ų, ρ_X-ray = 4.74 g/cm³, and ρ_pycn = 4.70 ± 0.05 g/cm³. The data of an IR spectroscopic study of the cuprate manganites were presented.