15N-NMR Spectroscopy
After the proton and carbon, nitrogen is, with oxygen, the most impor tant atom in organic and especially bioorganic molecules. However, the development of nitrogen spectroscopy is indeed very recent. This is due to the fact that nitrogen-14, which is the naturally abundant iso tope, suffers, for structural studies, from the disadvantages inherent in nuclei
with a quadrupolar moment (Table 1.1). Actually, indirect 15N measurements were reported in the early days of double resonance spectroscopy and the first direct detection of 15N resonance signals at the natural abundance level was realized in 1964 (R 17) at 4.33 MHz 1 (~ 1T) using a 15 mm o.d. cell in the field sweep mode (~ 0.16 min- ). Signal-to-noise ratios only of 3-4 were obtained for neat liquids and this low sensitivity of the 15N resonance still remains the main dis advantage for 15 spectroscopy (Table 1.1). However, nitrogen-15 has, N probably more than any other nucleus, benefited from the advances of NMR technology, i.e. Fourier transformation, multinuclear facilities, wide-bore super conducting solenoids, and, with the new generation of spectrometers, 15N-NMR is entering the field of routine investigation. Nevertheless, in spite of these spectacular improvements, obtaining 15N spectra of diluted species or large biochemical molecules is often not very easy and a good knowledge of the relaxation properties pecu liar to 15N may be necessary in order to adjust the pulse sequences and the decoupler duty cycle correctly (Section 2).
… full description
Saved in:
Bibliographic Details
-
Main Authors
-
Diehl, Peter,
Fluck, Ekkehard,
Kosfeld, Robert
-
Document Type
- eBook
-
Language
- English
-
Published
-
Berlin, Heidelberg
Springer Berlin / Heidelberg
1981
Springer Berlin Heidelberg
-
Edition
- 1
-
Series
- NMR Basic Principles and Progress
-
Subjects
-
ISBN
- 3642501745
9783642501746
9783540104599
3540104593
9783642501739
3642501737
-
ISSN
- 0170-5989
-
DOI
- 10.1007/978-3-642-50172-2
