Compară metode

	Secvența spin-echo (ecou de spin)	COSY	Spectrometria de masă FT-ICR	HSQC
Domeniu	Spectroscopie	Spectroscopie	Spectroscopie	Spectroscopie
Familie	Process / pipeline	Process / pipeline	Process / pipeline	Process / pipeline
Anul apariției	1950	1976	1974	1980
Autorul original	Erwin Hahn	Wüthrich Kurt	Alan Marshall	Anil Kumar
Tip	Spectroscopic pulse sequence	Two-dimensional pulse sequence	Mass spectrometry technique	Heteronuclear correlation sequence
Sursa seminală	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.	Comisarow, M. B., & Marshall, A. G. (1974). Fourier transform ion cyclotron resonance spectroscopy. Chemical Physics Letters, 25(2), 282-283.	Bodenhausen, G., & Ruben, D. J. (1981). Natural abundance nitrogen-15 NMR by enhanced heteronuclear spectroscopy. Chemical Physics Letters, 69(2), 185-189.
Denumiri alternative	CPMG pulse sequence, spin-echo NMR	COSY NMR, 2D COSY, 1H-1H COSY	FT-ICR-MS, Fourier Transform ICR, ICR mass spectrometry	HSQC NMR, 1H-13C HSQC, heteronuclear correlation
Înrudite	4	4	4	4
Rezumat	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.	Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry is an advanced analytical technique that combines magnetic confinement of ions with Fourier transform data processing to achieve exceptional mass accuracy and resolution. Developed by Comisarow and Marshall in 1974, FT-ICR-MS enables the determination of exact masses and elemental compositions of complex molecules, making it invaluable for environmental chemistry, metabolomics, petroleum characterization, and structural elucidation of unknowns.	Heteronuclear Single-Quantum Coherence (HSQC) is a 2D NMR technique that correlates proton and carbon-13 (or other heteronuclei) chemical shifts through one-bond coupling constants (1JHX). Developed in the early 1980s, HSQC rapidly became the workhorse of structural chemistry because it directly maps which carbons bear which protons, providing a comprehensive view of carbon skeleton connectivity and substitution patterns.