Representations of structural results

The reader should now appreciate that the use of fractional atomic coordinates to arrive at molecular geometry is straightforward. This is evident on inspection of crystal structure determinations in the scientific literature. The effects of thermal motion and slight disorder are illustrated by use of the computer program ORTEP. The amplitudes of 

FIGURE 11.9. An ORTEP diagram of an organic molecule (Ref. 25). (a) The thermal-ellipsoid plot, and (b) the chemical formula. The shaded lines in (a) are drawn parallel to the principal axes and highlight the cutaway portion of the ellipsoid. 

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