Compară metode

	ATR-FTIR	Secvența spin-echo (ecou de spin)	NOESY
Domeniu	Spectroscopie	Spectroscopie	Spectroscopie
Familie	Process / pipeline	Process / pipeline	Process / pipeline
Anul apariției	1961	1950	1981
Autorul original	Joop Fahrenfort	Erwin Hahn	Richard Ernst
Tip	Vibrational spectroscopy technique	Spectroscopic pulse sequence	Two-dimensional pulse sequence
Sursa seminală	Harrick, N. J. (1960). Study of physics of internal reflection from metals. Journal of Physics and Chemistry of Solids, 13(2), 143-155.	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.
Denumiri alternative	ATR-IR, attenuated total reflectance, FTIR spectroscopy	CPMG pulse sequence, spin-echo NMR	NOE spectroscopy, 2D NOESY, NOE NMR
Înrudite	3	4	3
Rezumat	Attenuated Total Reflectance (ATR) Fourier Transform Infrared (FTIR) spectroscopy is a variant of conventional FTIR that measures infrared absorption through evanescent-wave interrogation of samples in direct contact with a high-refractive-index crystal. Developed by Harrick and Fahrenfort in the 1960s, ATR-FTIR is now the dominant form of FTIR spectroscopy, enabling rapid, non-destructive characterization of organic compounds, polymers, coatings, and biological materials without extensive sample preparation.	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.	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.