1434 Journal of the American Chemical Society/100: 23/Nocember 8, 1978 solutions, the large magnetic field effect on the I3C enrichment, and the specificity of enrichment at the carbonyl carbon? The magnitude of the magnetic isotope effect may be computed from the expression P (the probability for formation of DBK from any radical pair), which is available from the theory of C1DNP: 2% 3
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