Effect Of Oxygen Stoichiometry In Lufe2o4-Delta And Its Microstructure Observed By Aberration-Corrected Transmission Electron Microscopy

A series of oxygen deficient LuFe2O4-delta materials have been prepared under a controlled oxygen partial-pressure atmosphere. Measurements of magnetization reveal that the increase of oxygen deficiencies could evidently depress the ferrimagnetic phase transition temperature (T-N). In additional to the well-known charge ordering within the (1 (1) over bar0) crystal plane, a visible structural modulation with q = (0, 1/4.2, 7/8) commonly appears on the (100) plane in the oxygen deficient samples. An aberration-corrected transmission electron microscopy study on the oxygen deficient samples demonstrates the presence of oxygen vacancies and local structural distortion. The atomic structural features in correlation with the structural modulation, distortion of the FeO5 polyhedron and the (001) twinning domains have been also examined.