Chemistry Reference
In-Depth Information
Figure 5.8
The first permanent electricmoments of some centrosymmetricmolecules
classified according to rules 3-7. It should be clear that the model can be
used only to predict stability of sufficiently symmetric configurations.
A total of 69 angular geometries of 35VdWdimers, classified according
to a tabulation like that illustrated in Figure 5.9, are collected in Table 5.4
and compared, when possible, with geometries resulting from
experiment, mostly by IR or microwave rotational spectra, or molecular
beam electric resonance spectra.
In the table, and also elsewhere in the present chapter, we use the
notation H-bonded to specify a structure bound by a hydrogen bond, and
anti-H-bonded to specify a structure where VdW binding is opposite to
that of a hydrogen bond.
We see from the table that the most stable angular geometries predicted
by the model agree almost perfectly with experiment. In a few cases, as for
