Periodic Table of Elements

Ac - Actinium

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Nuclides / Isotopes

Nuc-
lide
Atomic
Mass
NNAbun
%
SpinHalf LifeDMDTBR
%
Decay
Energy
(MeV)
Ac206 117Syn3+22msα   
meta state Syn10-33ms    
Ac207 118Syn9/2-22ms    
Ac208 119Syn3+95ms    
Ac209209.001120Syn9/2-0.10sαFr205~997.730
 0.10sεRa209~17.110
Ac210210.009121Syn 0.35sαFr206~967.610
 0.35sεRa210~48.200
Ac211211.008122Syn 0.25sαFr207~1007.620
Ac212212.0078123Syn 0.93sαFr208~977.520
 0.93sεRa212~37.480
Ac213213.0066124Syn 0.80sαFr209<=1007.500
Ac214214.007125Syn 8.2sαFr210>=897.350
 8.2sεRa214<=116.340
Ac215215.0065126Syn9/2-0.17sαFr21199.917.750
 0.17sεRa2150.093.490
Ac216216.0087127Syn1-~0.33msαFr212 9.243
meta state 0.037MeVSyn9-0.33msαFr212 9.280
Ac217217.0093128Syn9/2-69nsεRa217<=22.819
 69nsαFr213 9.832
Ac218218.0116129Syn1-1.08usαFr214 9.380
Ac219219.0124130Syn9/2-11.8usαFr215 8.830
Ac220220.0148131Syn3-26.4msεRa2200.000503.480
 26.4msαFr216 8.350
Ac221221.0156132Syn3/2-52msαFr217 7.780
Ac222222.0178133Syn1-5sαFr218997.137
 5sεRa22212.298
meta state 0.000MeVSyn 63sαFr218>=887.137
 63sITAc222<=10 
 63sεRa222>=0.702.298
Ac223223.0191134Syn5/2-2.10mαFr219996.783
 2.10mεRa22310.586
Ac224224.0217135Syn0-2.78hεRa22490.901.403
 2.78hαFr2209.106.327
 2.78hβ-Th224<1.600.232
Ac225225.0232136Syn3/2-10dαFr221 5.935
Ac226226.0261137Syn129.37hβ-Th226831.117
 29.37hεRa226170.640
 29.37hαFr2220.00605.536
Ac227227.0278138100.3/2-21.773yβ-Th22798.620.045
 21.773yαFr2231.385.042
Ac228228.031139Syn3+6.15hβ-Th228 2.127
Ac229229.0329140Syn3/2+62.7mβ-Th229 1.100
Ac230230.036141Syn1+122sβ-Th230 2.700
Ac231231.039142Syn1/2+7.5mβ-Th231 2.100
Ac232232.042143Syn1+119sβ-Th232 3.700
Ac233233.045144Syn1/2+145sβ-Th233  
Ac234234.048145Syn 44sβ-Th234  
Ac235 146Syn      
Ac236 147Syn      
NuclidePotential Parent Nuclides
Ac206None known
meta state None known
Ac207None known
Ac208None known
Ac209None known
Ac210None known
Ac211Pa215 (Syn)
Ac212Pa216 (Syn) Th212 (Syn)
Ac213Pa217 (Syn) Pa217m (Syn)
Ac214Pa218 (Syn)
Ac215Pa219 (Syn)
Ac216Pa220 (Syn) Th216 (Syn)
meta state 0.037MeVNone known
Ac217Pa221 (Syn)
Ac218Pa222 (Syn)
Ac219Pa223 (Syn)
Ac220Pa224 (Syn) Th220 (Syn)
Ac221Pa225 (Syn)
Ac222Ac222m (Syn) Pa226 (Syn)
meta state 0.000MeVNone known
Ac223Pa227 (Syn)
Ac224Pa228 (Syn)
Ac225Pa229 (Syn) Ra225 (Syn) Th225 (Syn)
Ac226Pa230 (Syn)
Ac227Pa231 (Natural) Ra227 (Syn)
Ac228Ra228 (Syn)
Ac229Ra229 (Syn)
Ac230Ra230 (Syn)
Ac231Ra231 (Syn)
Ac232Ra232 (Syn)
Ac233Ra233 (Syn)
Ac234Ra234 (Syn)
Ac235None known
Ac236None known

Key:

  • NN = Number of Neutrons
  • Abun % = Natural Abundance (as a percentage)
  • Syn = Synthetic Nuclide (does not occur in nature)
  • DM = Decay Mode
    α = Alpha emission
    β- = Beta emission
    β- β- = Double beta decay
    β+ = Positron emission
    ε = Electron Capture
    IT = Isomeric Transition
    N = Neutron emission
    P = Proton emission
    SF = Spontaneous Fission
  • DT = Decays To
  • BR % = Branch Ratio (as a percentage)

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