Path length

{
  "id": "MLC-T-CHM-008543",
  "term": "Path length",
  "field": "Chemistry",
  "definitions": [
    "The number of backbone atoms of a polymer that lie between two specified subunits. If a ring or ring system lies on the path, the shortest continuous run of atoms through that ring is the one counted. It is therefore an atom count along the chain, not a physical distance measured in nanometres or any other unit of length.",
    "The distance that light or other radiation travels through a sample or medium in a spectroscopic measurement. In absorption spectroscopy, it is the thickness of the sample cell through which the light beam passes. According to the Beer-Lambert law, absorbance is directly proportional to the path-length."
  ],
  "synonyms": [
    "path length"
  ],
  "subject": [
    "Polymer",
    "Analytical Chemistry"
  ],
  "see_also": [
    "optical path difference"
  ],
  "references": [
    "PAC, 2008, 80, 201. 'Structure-based nomenclature for cyclic organic macromolecules (IUPAC Recommendations 2008)' on page 205 (https://doi.org/10.1351/pac200880020201)",
    "PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 669 (https://doi.org/10.1515/pac-2019-0203)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/path-length/"
}