Comparer des méthodes

	Écho de spin RMN	COSY	NOESY
Domaine	Spectroscopie	Spectroscopie	Spectroscopie
Famille	Process / pipeline	Process / pipeline	Process / pipeline
Année d'origine	1950	1976	1981
Auteur d'origine	Erwin Hahn	Wüthrich Kurt	Richard Ernst
Type	Spectroscopic pulse sequence	Two-dimensional pulse sequence	Two-dimensional pulse sequence
Source fondatrice	Hahn, E. L. (1950). Spin echoes. Physical Review, 80(4), 580-594.	Aue, W. P., Bartholdi, E., & Ernst, R. R. (1976). Two-dimensional spectroscopy. Application to nuclear magnetic resonance. The Journal of Chemical Physics, 64(5), 2229-2246.	Aue, W. P., Bartholdi, E., & Ernst, R. R. (1976). Two-dimensional spectroscopy. Application to nuclear magnetic resonance. The Journal of Chemical Physics, 64(5), 2229-2246.
Alias	CPMG pulse sequence, spin-echo NMR	COSY NMR, 2D COSY, 1H-1H COSY	NOE spectroscopy, 2D NOESY, NOE NMR
Apparentées	4	4	3
Résumé	The spin-echo is a fundamental nuclear magnetic resonance (NMR) pulse sequence technique introduced by Erwin Hahn in 1950. It uses a 90-degree radiofrequency pulse followed by a 180-degree refocusing pulse to create an echo, effectively reversing the effects of magnetic field inhomogeneities and allowing accurate measurement of spin relaxation properties. This technique is essential in modern NMR spectroscopy for both one-dimensional and multidimensional experiments.	Correlation Spectroscopy (COSY) is a two-dimensional NMR technique that correlates proton chemical shifts through scalar coupling (J-coupling), revealing which protons are magnetically coupled and hence bonded through multiple bonds. Developed by Aue, Bartholdi, and Ernst in 1976, COSY became one of the most important tools in structural elucidation, enabling chemists to map out proton connectivity patterns and deduce molecular topology without isotopic labeling.	Nuclear Overhauser Enhancement Spectroscopy (NOESY) is a 2D NMR technique that detects through-space dipolar coupling between protons, rather than through-bond scalar coupling. Introduced by Macura and Ernst in 1981, NOESY reveals which protons are spatially close in the three-dimensional structure, independent of bonding connectivity. This makes NOESY invaluable for determining molecular conformation, assigning stereochemistry, and elucidating protein folds.