Collision diameter

{
  "id": "MLC-T-CHM-002222",
  "term": "Collision diameter",
  "field": "Chemistry",
  "definition": "The effective distance between the centers of two colliding particles at the point of closest approach during a head-on collision. It represents the minimum separation at which two particles are considered to be in contact. This parameter is used in kinetic theory to estimate collision frequencies and mean free paths in gases.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "collision cross-section",
    "collision theory"
  ],
  "references": [
    "Green Book, 2nd ed., p. 56 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/collision-diameter/"
}