13C

The Functions of 13C:

1. Low Natural Abundance: Carbon-13 has a low natural abundance, resulting in weak interactions between carbon atoms.

2. Influence of Protons: Despite its low natural abundance, the signal of carbon-13 is split by the high natural abundance of hydrogen-1.

3. Splitting Pattern: The splitting pattern of carbon-13 signals influenced by hydrogen-1 follows the 2nI+1 rule, where n is the number of equivalent hydrogen atoms coupled to the carbon atom. This splitting of signals reduces sensitivity.

4. Spin Number: Carbon-13 has a spin number (I) of 1/2.

5. Simplification through Decoupling: The splitting of carbon-13 signals can be simplified by decoupling from the frequencies of hydrogen-1.

6. Chemical Shift: The chemical shift of carbon-13 can help infer functional groups in molecules.

13C 的功能

   13C 的自然豐率太小，彼此之間影響微弱

   13C 的訊號卻受到自然豐率高的1H影響而分裂

   13C 訊號受1H影響的分裂模式符合2nI＋1 規則

           分裂的訊號使感度降低 

   13C  spin number I = 1/2  

   13C 的分裂訊號可以去耦合1H的頻率來簡化

   13C 的化學位移可助推斷官能基