Two Internal Rotational Degrees of Freedom

We now enumerate the ways in which this arbitrary conformation can be converted into an isometric structure. First, the enantiomorphic conformation can be obtained by reversing the signs of the torsion angles (pi- — 02- Second, because 

The map not only portrays the conformational space of a single isolated molecule but can also be used to plot observed torsion angles in particular structures. A collection of observed conformations will produce a scatter plot, and, according to the underlying structural correlation principle (see Chapter 5), the points will tend to congregate in regions of the conformational space associated with low energies. 

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