Universal Scales of Nitrogen Chemical Shifts

An alternative to the use of standard substances is to measure the absolute frequency given by the computer in FT spectroscopy. If samples of nearly equal susceptibilities are investigated (same solvent), the computer procedure enables us to compare the chemical shifts satisfactorily, provided that the same offset value of the RF pulse and the same lock system are used. The sensitivity is then enhanced since the space which would have been taken up by the coaxial cell can now be filled with sample. 

An attractive possibility is also offered by multinuclear spectroscopy. Taking advantage of the technical facilities of modern FT spectro- 

It has also been proposed to refer the resonance of a given nitrogen atom to that of proton assuming that TMS resonates at exactly 100 MHz (M 33). A detailed procedure of such a method is given in reference H 16. Thus, nitromethane resonates at 10 136 719 Hz (O.1M CDCl ) and 10 136 783 Hz (0.1M DMSO-dg) (B 69) since (CH ) (in DMSO-dg) is 

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