Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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64  Gd  152  151.9197995(18)    0.0020(1)     157.25(3)        g
        154  153.9208741(17)    0.0218(3)   
        155  154.9226305(17)    0.1480(12)  
        156  155.9221312(17)    0.2047(9)   
        157  156.9239686(17)    0.1565(2)   
        158  157.9241123(17)    0.2484(7)   
        160  159.9270624(18)    0.2186(19)  
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