So sánh phương pháp

	NOESY	COSY	Tán xạ Spin-Echo NMR
Lĩnh vực	Quang phổ học	Quang phổ học	Quang phổ học
Họ	Process / pipeline	Process / pipeline	Process / pipeline
Năm ra đời	1981	1976	1950
Người khởi xướng	Richard Ernst	Wüthrich Kurt	Erwin Hahn
Loại	Two-dimensional pulse sequence	Two-dimensional pulse sequence	Spectroscopic pulse sequence
Công trình gốc	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.	Hahn, E. L. (1950). Spin echoes. Physical Review, 80(4), 580-594.
Tên gọi khác	NOE spectroscopy, 2D NOESY, NOE NMR	COSY NMR, 2D COSY, 1H-1H COSY	CPMG pulse sequence, spin-echo NMR
Liên quan	3	4	4
Tóm tắt	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.	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.	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.