Turnover number

Term · Chemistry · MLC-T-CHM-013674

The number of times a catalyst or photocatalyst completes its cycle, usually quoted as moles of product formed per mole of catalyst or active site. It is a dimensionless count, not a rate, so it differs from the turnover frequency, which divides by time. In enzymology the same name has traditionally been used for the rate per active site, kcat, in reciprocal seconds.

Table 1. Record
Identifier	MLC-T-CHM-013674
Field	Chemistry
Subject	Physical and Biophysical Chemistry
References	PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 995 (https://doi.org/10.1351/PAC-REC-09-09-36)
See also	Heterogeneous photocatalysis; Homogeneous photocatalysis

Record as JSON

{
  "id": "MLC-T-CHM-013674",
  "term": "Turnover number",
  "field": "Chemistry",
  "definition": "The number of times a catalyst or photocatalyst completes its cycle, usually quoted as moles of product formed per mole of catalyst or active site. It is a dimensionless count, not a rate, so it differs from the turnover frequency, which divides by time. In enzymology the same name has traditionally been used for the rate per active site, kcat, in reciprocal seconds.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "heterogeneous photocatalysis",
    "homogeneous photocatalysis"
  ],
  "references": [
    "PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 995 (https://doi.org/10.1351/PAC-REC-09-09-36)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/turnover-number/"
}

Record 13,185 of 13,676 in Chemistry terminology (MLC-0109). Request the full dataset.