Spinning side-bands

Dipolar coupling and 3C shielding anisotropy cause unequal intensity of spinning side bands. The scalar coupling enabled magic angle rotation to distinguish two sets of sub-spectra.58... 

Figure 2. 13C NMR solid state difference spectra of (a) L. leucocephala and (b) T. aestivum (24) root tissue previously administered [1-13C] ferulic acid 5a. Fig. 2c shows the difference spectrum of a DHP polymer, derived from [1-13C] coniferyl alcohol 2a (29). CP/MAS spectra were obtained at 50 MHz on a Varian XL-200 Spectrophotometer equipped with a Doty Scientific MAS Probe. SSB = spinning side band.

It is seen that both the powder and the crystal show four distinct peaks, marked 1, 2, 3 and 4 in Fig. 11. The remaining peak(s)are the spinning side bands, as verified by the fact that their relative positions change in proportion to the spinning frequency. The doublet around 250 ppm can be assigned to... 

SQA in the form of a powder and b single crystal [26]. Note the narrower peaks in b. The peak numbering is the same as used in Fig. 1. The sharp line at 105 ppm corresponds to a spinning side band... 

Figure 13. NMR spectra at 35°C. of (a) low density lipoprotein lipids dispersed in D20 by sonication, 512 grams phosphorus/ml. (b) low density serum lipoproteins in 0.1 M Nad-D O, 625 grams lipid phosphorus/ml. (c) high density serum lipoproteins in 0.1 M NaCl-D/0, 832 pgrams lipid phosphorus/ml. Spectrum for high density lipoprotein lipids dispersed in water by sonication was essentially identical to (a). Spinning side bands are labeled S...

The corresponding H MAS-NMR spectra for the same samples are presented in Fig. 3a, 3b and 3c, respectively. As shown in Fig. 3a, the FI MAS-NMR spectrum of an unheated sepiolite consists of two distinct proton resonances centered near 0 ppm. A sharp resonance at higher field, which gives rise to only a few spinning side bands, is assigned to... 

Fig. 10. Proton NMR spectra at 220 Me of cyanoferriporphin and porphin zinc(II). The lines between —4.5 and —9.5 ppm correspond to the solvent resonances and their spinning side-bands...

Fig. 14. Proton NMR spectrum at 220 Me of cyanoferrimyoglobin. Different scales were used for the different spectral regions. Between DSS and —10 ppm there are ca. 1000 protons of the protein, whereas the intensities of the resolved lines in the regions —10 to —25 ppm, and DSS to +10 ppm correspond to one to three protons. The sharp lines between —3.8 and 6 ppm are the resonance of HDO and its first and second spinning side bands. Protoheme IX and the axial ligands of the heme iron in MbUICN are shown at the bottom. (Reproduced from ref. (115))...

A number of other features apparent in the toluene proton spectrum are worthy of note at this stage. Each absorption is accompanied by a number of small satellite peaks equally spaced on either side of the main absorptions. These may be spinning side-bands or 13C satellites (p. 342). The spinning side-bands are caused by inhomogeneities in the magnetic field and in the sample tube. They... 

Figure 7.6. Solid-state 13C NMR spectra of HF-treated material obtained from a grassland soils after ceasing annual burning for 22 years. Asterisks indicate spinning side bands.

Hong, J., and Harbison, G. S. (1993). Magic-angle-spinning side-band elimination by temporary interruption of the chemical-shift. /. Magn. Reson. Ser. A 105,128-136. 

Extensive spinning side bands are found and analyzed for the dimethyl derivative whereas the dibutyldistannaoxane does not show any such bands. 

FIGURE 3.7 Signal of neat chloroform with spinning side bands produced by spinning rate of 6 Hz, (a), and 14 Hz (b). (From Bovey, F. A. (1969). NMR Spectroscopy. New York Academic Press. With permission.)... 

XH line shape, resolution, and spinning side band test 3 % of chloroform in acetone-rf6 ... 

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