Leffler-Hammond rule

Chemical intuition, which is very useful in the location of minima, usually fails in the search for saddle points. The symmetry of the transition-state structure was discussed and it was shown that many transition states exhibit low symmetry (130-132). Some empirical rules have been developed for approximate localization of the transition state. The rule referred to in the literature as the Bell-Evans- Polanyi-Leffler-Hammond rule is well known the more exoergic the process, the more the transition-state geometry resembles that structure which belongs to a higher energy minimum on the given potential energy surface. This idea has been supported by calculations on SN2-activated complexes (133). 

ACIDITY FUNCTION BUNNETT-OLSEN EQUATIONS DECREE OF DISSOCIATION HAMMETT EQUATION HAMMOND PRINCIPLE/POSTULATE LEFFLER S ASSUMPTION REACTING BOND RULES HANES PLOT... 

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