השוואת שיטות

	הד-ספין ב-NMR	ספקטרומטריית מס (Mass Spectrometry) מסוג FT-ICR	HSQC
תחום	ספקטרוסקופיה	ספקטרוסקופיה	ספקטרוסקופיה
משפחה	Process / pipeline	Process / pipeline	Process / pipeline
שנת המקור	1950	1974	1980
הוגה השיטה	Erwin Hahn	Alan Marshall	Anil Kumar
סוג	Spectroscopic pulse sequence	Mass spectrometry technique	Heteronuclear correlation sequence
מקור מכונן	Hahn, E. L. (1950). Spin echoes. Physical Review, 80(4), 580-594.	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.
כינויים	CPMG pulse sequence, spin-echo NMR	FT-ICR-MS, Fourier Transform ICR, ICR mass spectrometry	HSQC NMR, 1H-13C HSQC, heteronuclear correlation
קשורות	4	4	4
תקציר	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.	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.