https://doi.org/10.1351/goldbook.S05567
A quantitative representation of , expresses the reactivity of a specified position in the aromatic compound PhX relative to that of a single position in benzene, then the (expressing discrimination between p- and m-positions in PhX) is defined as:
selectivity
in aromatic
substitution reactions
(usually electrophilic
, for monosubstituted benzene derivatives). If the partial rate factor
, selectivity
factor