Isotope Mass Abundance Spin Mag Moment
63Cu 62.939598 69.17% 3/2 +2.2233 65Cu 64.927793 30.83% 3/2 +2.3817
Cu I Ground State 1s22s22p63s23p63d104s 2S1/2 Ionization energy 62317.44 cm-1 (7.72638 eV) Ref. SM90 Cu II Ground State 1s22s22p63s23p63d10 1S0 Ionization energy 163669.2 cm-1 (20.2924 eV) Ref. SM90