Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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1   H   1    1.00782503223(9)   0.999885(70)  [1.00784,1.00811]  m
    D   2    2.01410177812(12)  0.000115(70)
    T   3    3.0160492779(24)               
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