Term: Koppel–Palm solvent parameters
https://doi.org/10.1351/goldbook.K03412

Definition:
Parameters to measure separately the ability of a solvent to enter into non-specific solvent–solute interactions (permittivity ɛ and refractive index η D) and specific solvent–solute interaction (solvent basicity or nucleophilicity B and solvent acidity or electrophilicity E) as contributing to overall solvent polarity.

Related Terms:
1) permittivity (http://doi.org/10.1351/goldbook.P04507).
2) refractive index (http://doi.org/10.1351/goldbook.R05240).
3) basicity (http://doi.org/10.1351/goldbook.B00611).
4) nucleophilicity (http://doi.org/10.1351/goldbook.N04251).
5) acidity (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.A00079).
6) electrophilicity (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.E02021).
7) polarity (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.P04710).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1134 (https://doi.org/10.1351/pac199466051077)

Citation: 'Koppel–Palm solvent parameters' 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.K03412

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