H Home Background Color: He Li Be Actinium Main Page Black White Gray B C N O F Ne Na Mg Actinium Pictures Page Al Si P S Cl Ar K Ca Actinium Technical Data Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og

Isotopes of Actinium (click to see decay chain): 206Ac  207Ac  208Ac  209Ac  210Ac  211Ac  212Ac  213Ac  214Ac  215Ac  216Ac  217Ac  218Ac  219Ac  220Ac  221Ac  222Ac  223Ac  224Ac  225Ac  226Ac  227Ac  228Ac  229Ac  230Ac  231Ac  232Ac  233Ac  234Ac  235Ac  236Ac

209Ac     Half-life Boson, 89p 120n 100 ms Spin 9/2 Parity -1 Hide Decay Modes Probability Mode Decay Energy Daughter 99% α 7.7292MeV 205Fr 1% β+ 5.9673MeV 209Ra Hide Ultimate Decay Products Yield Nuclide 70.75634403281% 197Au 28.833371496% 201Hg 1.400911151649% 205Tl 0.00007029% 193Ir 7.029×10-12% 189Os Atomic Weight 209.009494863 Abundance None Mass Excess 8.844409MeV Binding Energy 7.695847MeV Magnetic Moment N/A Quadrupole Moment N/A   Show Element Pictures. Also show decay chains leading to this isotope. Show only decays with probability >0.1%. Show Decay Image Smaller.

Click any isotope in diagram to see its data. Decay chain image generated by Mathematica's GraphPlot and IsotopeData functions from Wolfram Research, Inc..