Isotop aktinium

**[[Aktinium]]** (**<sub>89</sub>Ac**) tidak memiliki satu pun isotop stabil dan tidak memiliki komposisi isotop terestrial yang khas, sehingga berat atom standarnya tidak dapat diberikan. Ada 32 isotop aktinium yang diketahui, mulai dari 205Ac hingga 236Ac, dan 7 isomer. Tiga isotop ditemukan di alam, <sup>225</sup>Ac, 227Ac dan 228Ac, sebagai produk peluruhan antara dari, masing-masing, <sup>237</sup>Np, <sup>235</sup>U, dan <sup>232</sup>Th. 228Ac dan 225Ac sangat jarang, jadi hampir seluruh aktinium alami merupakan 227Ac.

Isotop aktinium yang paling stabil adalah 227Ac dengan waktu paruh 21,772 tahun, 225Ac dengan waktu paruh 10,0 hari, dan 226Ac dengan waktu paruh 29,37 jam. Semua isotop lain memiliki waktu paruh di bawah 10 jam, dan sebagian besar di bawah satu menit. Isotop berumur paling pendek yang diketahui adalah 217Ac dengan waktu paruh nanodetik.

227Ac yang dimurnikan akan mencapai kesetimbangan dengan produk peluruhannya (227Th dan 223Fr) setelah 185 hari.

## Daftar isotop

|-
|205Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 116
|
| 20(+97−9)&nbsp;mdtk
| α
| 201Fr
|
|
|-
| 206Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 117
| 206,01450(8)
| 25(7)&nbsp;mdtk
|
|
| (3+)
|
|-
| style="text-indent:1em" | 206m1Ac
|
| colspan="3" style="text-indent:2em" | 80(50) keV
| 15(6)&nbsp;mdtk
|
|
|
|
|-
| style="text-indent:1em" | 206m2Ac
|
| colspan="3" style="text-indent:2em" | 290(110)# keV
| 41(16)&nbsp;mdtk
|
|
| (10−)
|
|-
| 207Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 118
| 207,01195(6)
| 31(8)&nbsp;mdtk[27(+11−6)&nbsp;mdtk]
| α
| 203Fr
| 9/2−#
|
|-
| rowspan=2|208Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 119
| rowspan=2|208,01155(6)
| rowspan=2|97(16)&nbsp;mdtk[95(+24−16)&nbsp;mdtk]
| α (99%)
| 204Fr
| rowspan=2|(3+)
| rowspan=2|
|-
| β+ (1%)
| 208Ra
|-
| rowspan=3 style="text-indent:1em" | 208mAc
| rowspan=3|
| rowspan=3 colspan="3" style="text-indent:2em" | 506(26) keV
| rowspan=3|28(7)&nbsp;mdtk[25(+9−5)&nbsp;mdtk]
| α (89%)
| 204Fr
| rowspan=3|(10−)
| rowspan=3|
|-
| IT (10%)
| 208Ac
|-
| β+ (1%)
| 208Ra
|-
| rowspan=2|209Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 120
| rowspan=2|209,00949(5)
| rowspan=2|92(11)&nbsp;mdtk
| α (99%)
| 205Fr
| rowspan=2|(9/2−)
| rowspan=2|
|-
| β+ (1%)
| 209Ra
|-
| rowspan=2|210Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 121
| rowspan=2|210,00944(6)
| rowspan=2|350(40)&nbsp;mdtk
| α (96%)
| 206Fr
| rowspan=2|7+#
| rowspan=2|
|-
| β+ (4%)
| 210Ra
|-
| rowspan=2|211Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 122
| rowspan=2|211,00773(8)
| rowspan=2|213(25)&nbsp;mdtk
| α (99,8%)
| 207Fr
| rowspan=2|9/2−#
| rowspan=2|
|-
| β+ (0,2%)
| 211Ra
|-
| rowspan=2|212Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 123
| rowspan=2|212,00781(7)
| rowspan=2|920(50)&nbsp;mdtk
| α (97%)
| 208Fr
| rowspan=2|6+#
| rowspan=2|
|-
| β+ (3%)
| 212Ra
|-
| rowspan=2|213Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 124
| rowspan=2|213,00661(6)
| rowspan=2|731(17)&nbsp;mdtk
| α
| 209Fr
| rowspan=2|(9/2−)#
| rowspan=2|
|-
| β+ (langka)
| 213Ra
|-
| rowspan=2|214Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 125
| rowspan=2|214,006902(24)
| rowspan=2|8,2(2)&nbsp;dtk
| α (89%)
| 210Fr
| rowspan=2|(5+)#
| rowspan=2|
|-
| β+ (11%)
| 214Ra
|-
| rowspan=2|215Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 126
| rowspan=2|215,006454(23)
| rowspan=2|0.17(1)&nbsp;dtk
| α (99,91%)
| 211Fr
| rowspan=2|9/2−
| rowspan=2|
|-
| β+ (0,09%)
| 215Ra
|-
| rowspan=2|216Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 127
| rowspan=2|216,008720(29)
| rowspan=2|0,440(16)&nbsp;mdtk
| α
| 212Fr
| rowspan=2|(1−)
| rowspan=2|
|-
| β+ (7%)
| 216Ra
|-
| style="text-indent:1em" | 216mAc
|
| colspan="3" style="text-indent:2em" | 44(7) keV
| 443(7)&nbsp;µdtk
|
|
| (9−)
|
|-
| rowspan=2|217Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 128
| rowspan=2|217,009347(14)
| rowspan=2|69(4)&nbsp;ndtk
| α (98%)
| 213Fr
| rowspan=2|9/2−
| rowspan=2|
|-
| β+ (6,9%)
| 217Ra
|-
| style="text-indent:1em" | 217mAc
|
| colspan="3" style="text-indent:2em" | 2012(20) keV
| 740(40)&nbsp;ndtk
|
|
| (29/2)+
|
|-
| 218Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 129
| 218,01164(5)
| 1,08(9)&nbsp;µdtk
| α
| 214Fr
| (1−)#
|
|-
| style="text-indent:1em" | 218mAc
|
| colspan="3" style="text-indent:2em" | 584(50)# keV
| 103(11)&nbsp;ndtk
|
|
| (11+)
|
|-
| rowspan=2|219Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 130
| rowspan=2|219,01242(5)
| rowspan=2|11,8(15)&nbsp;µdtk
| α
| 215Fr
| rowspan=2|9/2−
| rowspan=2|
|-
| β+ (10−6%)
| 219Ra
|-
| rowspan=2|220Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 131
| rowspan=2|220,014763(16)
| rowspan=2|26,36(19)&nbsp;mdtk
| α
| 216Fr
| rowspan=2|(3−)
| rowspan=2|
|-
| β+ (5%)
| 220Ra
|-
| 221Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 132
| 221,01559(5)
| 52(2)&nbsp;mdtk
| α
| 217Fr
| 9/2−#
|
|-
| rowspan=2|222Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 133
| rowspan=2|222,017844(6)
| rowspan=2|5,0(5)&nbsp;dtk
| α (99%)
| 218Fr
| rowspan=2|1−
| rowspan=2|
|-
| β+ (1%)
| 222Ra
|-
| rowspan=3 style="text-indent:1em" | 222mAc
| rowspan=3|
| rowspan=3 colspan="3" style="text-indent:2em" | 200(150)# keV
| rowspan=3|1,05(7)&nbsp;mnt
| α (88,6%)
| 218Fr
| rowspan=3|tinggi
| rowspan=3|
|-
| IT (10%)
| 222Ac
|-
| β+ (1,4%)
| 222Ra
|-
| rowspan=3|223Ac
| rowspan=3|
| rowspan=3 style="text-align:right" | 89
| rowspan=3 style="text-align:right" | 134
| rowspan=3|223,019137(8)
| rowspan=3|2,10(5)&nbsp;mnt
| α (99%)
| 219Fr
| rowspan=3|(5/2−)
| rowspan=3|
|-
| EC (1%)
| 223Ra
|-
| CD (3,2%)
| ***<sup>209</sup>Bi***<sup>14</sup>C
|-
| rowspan=3|224Ac
| rowspan=3|
| rowspan=3 style="text-align:right" | 89
| rowspan=3 style="text-align:right" | 135
| rowspan=3|224,021723(4)
| rowspan=3|2,78(17)&nbsp;jam
| β+ (90,9%)
| 224Ra
| rowspan=3|0−
| rowspan=3|
|-
| α (9,1%)
| 220Fr
|-
| β− (1,6%)
| 224Th
|-
| rowspan=2|<sup>225</sup>Ac
| rowspan=2|
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 136
| rowspan=2|225,023230(5)
| rowspan=2|10,0(1)&nbsp;hri
| α
| 221Fr
| rowspan=2|(3/2−)
| rowspan=2|Renik
|-
| CD (6%)
| 211Bi14C
|-
| rowspan=3|226Ac
| rowspan=3|
| rowspan=3 style="text-align:right" | 89
| rowspan=3 style="text-align:right" | 137
| rowspan=3|226,026098(4)
| rowspan=3|29,37(12)&nbsp;jam
| β− (83%)
| 226Th
| rowspan=3|(1)(−#)
| rowspan=3|
|-
| EC (17%)
| 226Ra
|-
| α (0,006%)
| 222Fr
|-
| rowspan=2|227Ac
| rowspan=2|Aktinium
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 138
| rowspan=2|227,0277521(26)
| rowspan=2|21,772(3)&nbsp;thn
| β− (98,61%)
| 227Th
| rowspan=2|3/2−
| rowspan=2|Renik
|-
| α (1,38%)
| 223Fr
|-
| rowspan=2|228Ac
| rowspan=2|Mesotorium 2
| rowspan=2 style="text-align:right" | 89
| rowspan=2 style="text-align:right" | 139
| rowspan=2|228,0310211(27)
| rowspan=2|6,13(2)&nbsp;jam
| β−
| 228Th
| rowspan=2|3+
| rowspan=2|Renik
|-
| α (5,5%)
| 224Fr
|-
| 229Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 140
| 229,03302(4)
| 62,7(5)&nbsp;mnt
| β−
| 229Th
| (3/2+)
|
|-
| 230Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 141
| 230,03629(32)
| 122(3)&nbsp;dtk
| β−
| 230Th
| (1+)
|
|-
| 231Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 142
| 231,03856(11)
| 7,5(1)&nbsp;mnt
| β−
| 231Th
| (1/2+)
|
|-
| 232Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 143
| 232,04203(11)
| 119(5)&nbsp;dtk
| β−
| ***<sup>232</sup>Th***
| (1+)
|
|-
| 233Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 144
| 233,04455(32)#
| 145(10)&nbsp;dtk
| β−
| 233Th
| (1/2+)
|
|-
| 234Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 145
| 234,04842(43)#
| 44(7)&nbsp;dtk
| β−
| 234Th
|
|
|-
| 235Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 146
| 235,05123(38)#
| 60(4)&nbsp;dtk
| β−
| 235Th
| 1/2+#
|
|-
| 236Ac
|
| style="text-align:right" | 89
| style="text-align:right" | 147
| 236,05530(54)#
| 72(+345-33)&nbsp;dtk
| β−
| 236Th
|
|

## Referensi

* Massa isotop dari:
**
* Komposisi isotop dan massa atom standar dari:
**
**
* Data waktu paruh, spin, dan isomer dipilih dari sumber-sumber berikut.
**
**
**