Atomic Weights and Isotopic Compositions for Carbon
Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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6   C   12   12.0000000(00)     0.9893(8)     [12.0096,12.0116]   
        13   13.00335483507(23)  0.0107(8)   
        14   14.0032419884(40)              
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