HSAB principle exceptions

A number of HSAB-pertinent organochemical subjects which have not been discussed in the previous chapters will now be considered. Again the selection of topics is arbitrary, illustrative rather than comprehensive. Some notable exceptions to the HSAB principle are also presented. 

For an empirical principle with its theoretical foundation yet to be firmly and thoroughly established, exceptions to its general validity are bound to exist. In the case of the HSAB principle, there are remarkably few. These exceptions may simply mirror our presently imperfect understanding of certain subtle bonding aspects or other undetermined factors. 

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