Isotop aktinium

Aktinium (₈₉Ac) 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, ²²⁵Ac, ²²⁷Ac dan ²²⁸Ac, sebagai produk peluruhan antara dari, masing-masing, ²³⁷Np, ²³⁵U, dan ²³²Th. 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) mdtk | α | ²⁰¹Fr | |

| ²⁰⁶Ac | | style="text-align:right" | 89 | style="text-align:right" | 117 | 206,01450(8) | 25(7) mdtk | | | (3+) |

| style="text-indent:1em" | ^206m2Ac | | colspan="3" style="text-indent:2em" | 290(110)# keV | 41(16) mdtk | | | (10−) |

| ²⁰⁷Ac | | style="text-align:right" | 89 | style="text-align:right" | 118 | 207,01195(6) | 31(8) mdtk
[27(+11−6) 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) mdtk
[95(+24−16) 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) mdtk
[25(+9−5) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) ndtk | | | (29/2)+ |

| ²¹⁸Ac | | style="text-align:right" | 89 | style="text-align:right" | 129 | 218,01164(5) | 1,08(9) µdtk | α | ²¹⁴Fr | (1−)# |

| style="text-indent:1em" | ^218mAc | | colspan="3" style="text-indent:2em" | 584(50)# keV | 103(11) 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) 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) 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) 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) 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) 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) mnt | α (99%) | ²¹⁹Fr | rowspan=3|(5/2−) | rowspan=3|

| EC (1%) | ²²³Ra

| CD (3,2%) | ²⁰⁹Bi
¹⁴C

| 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) jam | β⁺ (90,9%) | ²²⁴Ra | rowspan=3|0− | rowspan=3|

| α (9,1%) | ²²⁰Fr

| β⁻ (1,6%) | ²²⁴Th

| rowspan=2|²²⁵Ac | 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) hri | α | ²²¹Fr | rowspan=2|(3/2−) | rowspan=2|Renik

| CD (6%) | ²¹¹Bi
¹⁴C

| 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) 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) 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) 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) mnt | β⁻ | ²²⁹Th | (3/2+) |

| ²³⁰Ac | | style="text-align:right" | 89 | style="text-align:right" | 141 | 230,03629(32) | 122(3) dtk | β⁻ | ²³⁰Th | (1+) |

| ²³¹Ac | | style="text-align:right" | 89 | style="text-align:right" | 142 | 231,03856(11) | 7,5(1) mnt | β⁻ | ²³¹Th | (1/2+) |

| ²³²Ac | | style="text-align:right" | 89 | style="text-align:right" | 143 | 232,04203(11) | 119(5) dtk | β⁻ | ²³²Th | (1+) |

| ²³³Ac | | style="text-align:right" | 89 | style="text-align:right" | 144 | 233,04455(32)# | 145(10) dtk | β⁻ | ²³³Th | (1/2+) |

| ²³⁴Ac | | style="text-align:right" | 89 | style="text-align:right" | 145 | 234,04842(43)# | 44(7) dtk | β⁻ | ²³⁴Th | |

| ²³⁵Ac | | style="text-align:right" | 89 | style="text-align:right" | 146 | 235,05123(38)# | 60(4) dtk | β⁻ | ²³⁵Th | 1/2+# |

| ²³⁶Ac | | style="text-align:right" | 89 | style="text-align:right" | 147 | 236,05530(54)# | 72(+345-33) 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.

Sumber dan atribusi

Konten artikel ini diadaptasi dari Wikipedia bahasa Indonesia, revisi 29029759 (2026-03-12T11:29:20Z), yang tersedia berdasarkan lisensi Creative Commons Atribusi-BerbagiSerupa (CC BY-SA). Mohon gunakan konten ini secara bijak serta sesuai dengan ketentuan lisensi yang berlaku.