Novel Titanium-Manganites of Lanthanum and Alkali Metals

Abstract

The titanium-manganites of LaMeI 2TiMnO6 (MeI — Li, Na, K) were synthesized by the ceramic technology with the high-temperature reaction of oxides of La2O3, TiO2, Mn2O3 with carbonates of Li2CO3, Na2CO3, K2CO3 within 800–1200 ºС. The X-ray diffraction methods demonstrated that all of them were crystallized in the cubic syngony with the lattice parameters such as LaLi2TiMnO6 — а = 13.480.02 Å, Vo = 2449.460.06 Å3, Z = 4, Vo el.cell = 612.870.02 Å3, roent. = 3.81; pick. = 3.780.03 g/cm3; LaNa2TiMnO6 — а = 14.060.02 Å, Vo = 2779.430,06 Å3, Z = 4, Vo el.cell = 694.960.02 Å3, roent. = 3.67; pick. = 3.650.01 g/cm3; LaK2TiMnO6 — а = 14.740.02 Å, Vo = 3202.520.06 Å3, Z = 4, Vo el.cell = 800.520.02 Å3, roent. = 3.45;  pick. = 3.430.01 g/cm3. Correctness and authenticity of the results on the indexing of X-ray photographs of titanium-manganite were confirmed with the good experimental and calculated values (104/d2), the pycnometric and X-ray densities, and also the theoretical and experimental values of cell volumes. The rising of values of the lattice parameters of the synthesized titanium-manganites was determined with increasing in the ionic radii from Li to K.