In NMR spectroscopy, receptivity refers to the relative detectability of a particular element. Some elements are easily detected, some less so. The receptivity is a function of the abundance of the element's NMR-responsive isotope and that isotope's gyromagnetic ratio (or equivalently, the nuclear magnetic moment). Some isotopes, tritium for example, have large gyromagnetic ratios but low abundance. Other isotopes, for example 103Rh, are highly abundant but have low gyromagnetic ratios. Widely used NMR spectroscopies often focus on highly receptive elements: 1H, 19F, and 31P. [1]
| Isotope | Natural abundance (%) | Magnetogyric Ratio (107 rad⋅s−1⋅T−1) | Receptivity vs 13C (RC) | |
|---|---|---|---|---|
| 0 | 28.5 | - | ||
| 1H | 99 | 26.8 | 5700 | |
| 13C | 1.11 | 6.7 | 1 | |
| 19F | 100 | 25.1 | 4700 | |
| 31P | 100 | 10.8 | 377 | |
| 77Se | 7.58 | 5.10 | 3.0[2] | |
| 103Rh | 100 | -0.84 | 0.18 |