Yukawa–Tsuno equation

https://doi.org/10.1351/goldbook.Y06734
A multiparameter extension of the Hammett equation to quantify the role of enhanced resonance effect on the reactivity of meta- and para-substituted benzene derivatives, e.g. log10⁡k=log10⁡k0+ρ [σ+r (σ+−σ)] The parameter r gives the enhanced resonance effect on the scale (σ+−σ) or (σ−σ), respectively.
See also: ρ-value, σ-constant
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1176 [Terms] [Paper]
Citation: 'Yukawa–Tsuno equation' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.Y06734 RIS BibTex EndNote
Div. IIIPDFTextXMLJSON
Last revised: February 24, 2014