Title: spin-lattice relaxation
Long Title: IUPAC Gold Book - spin-lattice relaxation
DOI: 10.1351/goldbook.08422
Status: current

Definition
Mechanism in nuclear magnetic resonance spectroscopy by which the component of the magnetization vector along the direction of the static magnetic induction reaches thermodynamic equilibrium with its surroundings through loss of energy of the excited nuclear spins to the surrounding molecular lattice. The resultant exponential decay of signal is characterized by the spin-lattice relaxation time \(T_{1}\) (reciprocal of the rate constant of this mechanism).

Note
\(T_{1}\) dictates the time required between individual NMR scans to ensure the system has returned to equilibrium.

Related Terms
- nuclear magnetic resonance spectroscopy: https://goldbook.iupac.org//terms/view/08218
- spin-lattice relaxation time: https://goldbook.iupac.org//terms/view/08423

Source
- PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 706 (https://doi.org/10.1515/pac-2019-0203)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08422/html
- json: https://goldbook.iupac.org/terms/view/08422/json
- xml: https://goldbook.iupac.org/terms/view/08422/xml

Citation: Citation: 'spin-lattice relaxation' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.08422
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Accessed: 2026-06-21T04:02:31+00:00