Phase Equilibria in the Li–Mn–Eu–O System.

Phase equilibria in the Li–Mn–Eu–O system were studied for the first time in the temperature range 700–1000°С, and a concentration diagram was constructed within the Li–Mn–Eu triangle at an oxygen partial pressure of 21 kPa. It was shown that the LiEuO2–Li2MnO3 section can be represented as quasi-binary, unlike the sections LiEuO2–LiMnO2 and LiEuO2–LiMn2O4. It was determined that the isomorphic substitution of Eu for Mn in spinel LiMn2O4 (Fd m) does not exceed 2 mol %, while Li2MnO3 (C2/m) loses its single-phase character. [ABSTRACT FROM AUTHOR]