Correction Factors Summary and Speculations

There are a number of these [3], and the two types of benzofusion hsted here are extensive, leading to regularities among the most striking so far encountered. 

Benzofusion to Give Benzenoid Structures in Six-Membered Ring Oxoheterocycies 

Benzofusion to Give Quinonoid Structures in a Variety of Compounds 

Other areas in which correction factors have proved useful in systematizing existing data include [3] N,N-lone pair repulsion in six-membered heterocyclic rings the tautomerism of symmetrical, that is, aliphatic, and heterocyclic, that is, asymmetrical, amidines and the removal of apparent anomalies in several sorts of LFER relationship whose origin lay in the need for pfQ corrections that varied with the compound structure. In these cases and others, however, so many other factors are involved that it has proved impossible to isolate successfully the contribution due to this one alone. 

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