Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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34  Se  74   73.922475934(15)   0.0089(4)     78.971(8)        r
        76   75.919213704(17)   0.0937(29)  
        77   76.919914154(67)   0.0763(16)  
        78   77.91730928(20)    0.2377(28)  
        80   79.9165218(13)     0.4961(41)  
        82   81.9166995(15)     0.0873(22)  
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