Isotope Mass Abundance Spin Mag Moment
54Fe 53.939612 5.82% 0 56Fe 55.934939 91.18% 0 57Fe 56.935396 2.1 % 1/2 +0.09044 58Fe 57.933277 0.28% 0
Fe I Ground State 1s22s22p63s23p63d64s2 5D4
Ionization energy 63737 cm-1 (7.9024 eV) Ref. SC85
Fe II Ground State 1s22s22p63s23p63d64s 6D9/2
Ionization energy 130563 cm-1 (16.1877 eV) Ref. SC85