Long spacing

{
  "id": "MLC-T-CHM-006763",
  "term": "Long spacing",
  "field": "Chemistry",
  "definition": "The repeat distance in a semi-crystalline polymer, comprising one crystalline lamella and one amorphous layer. This periodic structure gives rise to a distinct diffraction or scattering peak at small angles in X-ray or neutron scattering experiments. The value of the long spacing, which is on the order of 10 to 100 nanometers, depends on the crystallization conditions, such as temperature and cooling rate.",
  "subject": "Polymer",
  "see_also": [
    "angle",
    "diffraction",
    "neutron"
  ],
  "references": [
    "Purple Book, 1st ed., p. 82 (http://old.iupac.org/publications/books/author/metanomski.html)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/long-spacing/"
}