Term: relaxation time
https://doi.org/10.1351/goldbook.R05287

Definition:
In magnetic resonance spectroscopy the longitudinal relaxation time, T 1, is associated with spin-lattice relaxation, and the transverse relaxation time, T 2, with spin-spin relaxation. The definitions are: dMz/dt = (-Mz - Mz,e)/T1 and dMx/dt = -Mx/T2, where M z and M x are the components of magnetization parallel and perpendicular to the static field B and the subscript e denotes the equilibrium value.

Related Terms:
1) resonance (http://doi.org/10.1351/goldbook.R05326).
2) spectroscopy (http://doi.org/10.1351/goldbook.S05848).
3) relaxation (http://doi.org/10.1351/goldbook.R05285).

Source: Green Book, 2nd ed., p. 25 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'relaxation time' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.R05287

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