### Atomic Data for Neptunium (Np)

### Atomic Number = 93

### Atomic Weight = 237.0482

### Reference = E95

    Isotope    Mass        Abundance Spin Mag Moment

    237Np      237.048167  0         5/2  +3.14

    Np I  Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p65f46d7s2  6L11/2
          Ionization energy  50536 cm-1 (6.2657 eV)   Ref. KDEE97

    Np II Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p65f46d7s  7L5