OBLIQUE TEXTURE ELECTRON DIFFRACTION OTED

Let us suppose that the exploited cleavage is 001 and the cleavage lamellae are textured in a planar mount so that their orientations have a common perpendicular to (001), 

Note that in the OTED method the overlap of reflections is limited to those reflections with the same value of Dhki (Eqn. 3) and belonging to the same ellipse thus a dramatic improvement is obtained relative to the classic powder diffraction methods. Note also that, in the most general case, the reflections with / = 0 do not lie on the minor axis because the a b and ab planes are not coincident. These two planes coincide in orthogonal crystal systems where Equations (3) and (4) become, in the order. 

Each ellipse is characterized by h + = constant. Table 3 reports the absolute 

These are the rows with h = 0(mod3) and k =0(mod3) they are family rows in the Pauling model and are common to all polytypes of the same family. 

Ellipse order m 3lF + ld Type of ellipse Ellipse order m 3tF + kf Type of ellipse 

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