The @[email protected] \[\log _{10}k_{\text{N}} = \log _{10}k_{0}+N_{\text{+}}\] applied to the reactions between nucleophiles and certain large and relatively @[email protected] organic cations, e.g. arenediazonium, triarylmethyl and aryltropylium cations in various solvents. \(k_{\text{N}}\) is the @[email protected] for reaction of a given @[email protected] with a given nucleophilic system (i.e. given nucleophile in a given solvent). \(k_{0}\) is the @[email protected] for the same @[email protected] with water in water, and \(N_{\text{+}}\) is a parameter which is characteristic of the nucleophilic system and independent of the @[email protected] A surprising feature of the equation is the absence of a @[email protected] of \(N_{\text{+}}\), characteristic of the substrate (cf. the \(s\) in the @[email protected]), even though values of \(N_{\text{+}}\) vary over 13 log units. The equation thus involves a gigantic breakdown of the @[email protected] The equation has been extended both in form and in range of application.
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1161 [Terms] [Paper]