Defect structures of iron oxides

Many properties of solid, in greater extent, are correlated with the weeny differences between the crystal structure of it and that of the ideal one. An ideal crystal means the lattice of which shows order entirely. Atoms in such crystal lattice are inactive and the electrons in it are arranged according to the minimmn energy state. 

Practical crystals may have several kinds of defects and one kind of which would be caused by the increasing of atomic amplitude and the others by variable electron arrangements in accordance with the possible energy levels. Combination of a series of atomic defects may also forms the linear incompleteness i.e., displacement. 

Defect structures of oxides are the most interested regions in the study of solids. The reasons are that first, the various defects, as discussed in the following context, could be observed from the oxides, which offer wide base of substances for discussion theoretically. Second, oxides are the basic substances of a variety of matters and are important components of catalyst. To study the oxide catalysts or metal catalysts with oxides as precursors in depth and defect structure of oxide itself has, ever since, been the important theoretical foundations for the discussion of relation between the structure and catalytic performances of catalysts. Yue Wu ° considered that compared with ordinary defect structures, the followings have particular meanings for catalysis studies  

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