How can 14^N be NMR active if it has 7 N and 7 Protons? I understood the text as both must be even numbers for the nucleus to be active (TA). (Not quite. If the number of neutrons and protons is odd, the nucleus is always magnetic, because the magnetic moments of individual nuclei can not compensate for each other. If this number is even, they usually do, and the nucleus is not magnetic. Sometimes, the magnetic moments of nuclei are aligned (two nuclei have the same magnetic moments, instead of the opposite moments), and then the nucleus is magnetic. 14N is an example (so-called quadrupole nucleus). Another simpler example is deuterium (2H) - GS.
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