### Atomic Data for Europium (Eu)

### Atomic Number = 63

### Atomic Weight = 151.965

### Reference = E95

    Isotope    Mass        Abundance Spin Mag Moment

    151Eu      150.919847  47.8%     5/2  +3.464
    153Eu      152.921225  52.2%     5/2  +1.530

    Eu I  Ground State (1s22s22p63s23p63d104s24p64d105s25p6)4f76s2  8S°7/2
          Ionization energy  45734.74 cm-1 (5.67038 eV)   Ref. NRCA00

    Eu II Ground State (1s22s22p63s23p63d104s24p64d105s25p6)4f76s  9S°4
          Ionization energy  90700 cm-1 (11.25 eV)   Ref. SR65