The layered material, Li-2/3[Mn1/3Fe2/3]O-2, Was prepared by Li ion exchange reactions in alcohols from the host, Na-2/3[Mn-1/3 Fe-2/3]O-2. The structure of the stacking sequence was determined via the simulation of X-ray diffraction patterns and its electrochemical properties were characterized. The stacking sequence of the products depended on the reaction temperature and time. The structure of Li-2/3[Mn1/3Fe2/3]O-2 obtained at 85 degreesC has stacking faults including the O3, O2, P2 type with the ratio of 4:4:2. The electrochemical properties of Li-2/3[Mn1/3Fe2/3]O-2 were studied using lithium cells. (C) 2003 Elsevier B.V. All rights reserved.