Refractive index increment

{
  "id": "MLC-T-CHM-010100",
  "term": "Refractive index increment",
  "field": "Chemistry",
  "definition": "The rate of change of the refractive index of a polymer solution with respect to the concentration of the polymer, measured at constant temperature, pressure, and wavelength of light. It is a specific property for a given polymer, solvent, and temperature combination. This value, denoted as dn/dc, is required for determining molar mass by static light scattering and is measured using a differential refractometer.",
  "subject": "Polymer",
  "see_also": [
    "refractive index",
    "volume fraction"
  ],
  "references": [
    "Purple Book, 1st ed., p. 65 (http://old.iupac.org/publications/books/author/metanomski.html)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/refractive-index-increment/"
}