Barium (Ba)
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Atomic Data for Barium (Ba)
Atomic Number = 56
Atomic Weight = 137.327
Reference E95
Isotope Mass Abundance Spin Mag Moment
130Ba 129.906282 0.11% 0
132Ba 131.905042 0.10% 0
134Ba 133.904486 2.42% 0
135Ba 134.905665 6.59% 3/2 +0.8365
136Ba 135.904553 7.85% 0
137Ba 136.905812 11.23% 3/2 +0.9357
138Ba 137.905232 71.70% 0
Ba I Ground State 1s22s22p63s23p63d104s24p64d105s25p66s2 1S0
Ionization energy 42034.91 cm-1 (5.211664 eV) Ref. PVHA85
Ba II Ground State 1s22s22p63s23p63d104s24p64d105s25p66s 2S1/2
Ionization energy 80686.30 cm-1 (10.00383 eV) Ref. KL99