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Why won't you see any carbon-carbon splitting in #C^13 NMR#?

Answer 1

Because the isotopic abundance of the carbon-13 nucleus is around 1%.

In simple terms, let's look at ethane, #H_3C-CH_3#.

A spin active carbon nucleus will make up about 1% of the sample, and 1% of this 1% will contain two spin active carbon nuclei. Since these isotopomers are not significantly abundant, these absorptions will probably fade into the baseline (be weaker than the intensity of the background noise).

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Answer 2

Jacob Anderson

In C^13 NMR, you won't see any carbon-carbon splitting because the natural abundance of C^13 isotope is low, approximately 1.1%. Therefore, the probability of two adjacent carbon atoms both having C^13 nuclei is extremely low, making carbon-carbon splitting negligible in C^13 NMR spectra.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.