Z-value

{
  "id": "MLC-T-CHM-012820",
  "term": "Z-value",
  "field": "Chemistry",
  "definition": "A solvent polarity parameter derived from the solvatochromic shift of the charge-transfer absorption band of 1-ethyl-4-methoxycarbonylpyridinium iodide. This value quantifies the empirical solvent polarity, reflecting the ability of a solvent to stabilize charge separation. Z-values are expressed in kcal/mol and provide a measure of the overall polarity of a solvent, encompassing both its dielectric constant and hydrogen-bonding capabilities.",
  "synonyms": [
    "Kosower Z-value"
  ],
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "Dimroth-Reichardt ET parameter",
    "Grunwald-Winstein equation",
    "ionizing power",
    "wavelength"
  ],
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1176 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/z-value/"
}