Title: spin-spin relaxation
Long Title: IUPAC Gold Book - spin-spin relaxation
DOI: 10.1351/goldbook.08425
Status: current

Definition
Loss of magnetization in the \(xy\) plane (in the absence of \(\boldsymbol{B_{0}}\) inhomogeneities) through the interchange of energy between nuclear spins resulting in some precessing faster than the Larmor angular frequency and some slower.

Note
The resultant exponential decay of signal is characterized by the spin-spin relaxation time \(T_{2}\) (reciprocal of the rate constant of this mechanism).

Related Terms
- Larmor angular frequency: https://goldbook.iupac.org//terms/view/08375
- net dephasing time: https://goldbook.iupac.org//terms/view/08380
- spin-spin relaxation time: https://goldbook.iupac.org//terms/view/08426

Source
- PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 707 (https://doi.org/10.1515/pac-2019-0203)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08425/html
- json: https://goldbook.iupac.org/terms/view/08425/json
- xml: https://goldbook.iupac.org/terms/view/08425/xml

Citation: Citation: 'spin-spin 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.08425
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Accessed: 2026-06-21T02:23:28+00:00