Isotop serium

**[[Serium]]** (**<sub>58</sub>Ce**) yang terbentuk secara alami terdiri dari empat isotop stabil: 136Ce, 138Ce, 140Ce, dan 142Ce, dengan 140Ce sebagai yang paling melimpah (kelimpahan alami 88,48%) dan satu-satunya yang stabil secara teoretis; 136Ce, 138Ce, dan 142Ce diprediksi mengalami peluruhan beta ganda tetapi proses ini tidak pernah teramati. Ada 35 radioisotop yang telah dikarakterisasi, dengan yang paling stabil adalah 144Ce, dengan waktu paruh 284,893 hari; 139Ce, dengan waktu paruh 137,640 hari; dan 141Ce, dengan waktu paruh 32,501 hari. Semua isotop radioaktif yang tersisa memiliki waktu paruh kurang dari 4 hari dan sebagian besar memiliki waktu paruh kurang dari 10 menit. Unsur ini juga memiliki 10 keadaan meta.

Isotop serium memiliki berat atom berkisar dari 119 u (119Ce) hingga 157&nbsp;u (157Ce).

## Daftar isotop

|-
| 119Ce
| style="text-align:right" | 58
| style="text-align:right" | 61
| 118,95276(64)#
| 200#&nbsp;mdtk
| β<sup>+</sup>
| 119La
| 5/2+#
|
|
|-
| 120Ce
| style="text-align:right" | 58
| style="text-align:right" | 62
| 119,94664(75)#
| 250#&nbsp;mdtk
| β+
| 120La
| 0+
|
|
|-
| 121Ce
| style="text-align:right" | 58
| style="text-align:right" | 63
| 120,94342(54)#
| 1,1(1)&nbsp;dtk
| β+
| 121La
| (5/2)(+#)
|
|
|-
| rowspan=2|122Ce
| rowspan=2 style="text-align:right" | 58
| rowspan=2 style="text-align:right" | 64
| rowspan=2|121,93791(43)#
| rowspan=2|2# dtk
| β+
| 122La
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β+, p
| 121Ba
|-
| rowspan=2|123Ce
| rowspan=2 style="text-align:right" | 58
| rowspan=2 style="text-align:right" | 65
| rowspan=2|122,93540(32)#
| rowspan=2|3,8(2)&nbsp;dtk
| β+
| 123La
| rowspan=2|(5/2)(+#)
| rowspan=2|
| rowspan=2|
|-
| β+, p
| 122Ba
|-
| 124Ce
| style="text-align:right" | 58
| style="text-align:right" | 66
| 123,93041(32)#
| 9,1(12)&nbsp;dtk
| β+
| 124La
| 0+
|
|
|-
| rowspan=2|125Ce
| rowspan=2 style="text-align:right" | 58
| rowspan=2 style="text-align:right" | 67
| rowspan=2|124,92844(21)#
| rowspan=2|9,3(3)&nbsp;dtk
| β+
| 125La
| rowspan=2|(7/2−)
| rowspan=2|
| rowspan=2|
|-
| β+, p
| 124Ba
|-
| 126Ce
| style="text-align:right" | 58
| style="text-align:right" | 68
| 125,92397(3)
| 51,0(3)&nbsp;dtk
| β+
| 126La
| 0+
|
|
|-
| 127Ce
| style="text-align:right" | 58
| style="text-align:right" | 69
| 126,92273(6)
| 29(2)&nbsp;dtk
| β+
| 127La
| 5/2+#
|
|
|-
| 128Ce
| style="text-align:right" | 58
| style="text-align:right" | 70
| 127,91891(3)
| 3,93(2)&nbsp;mnt
| β+
| 128La
| 0+
|
|
|-
| 129Ce
| style="text-align:right" | 58
| style="text-align:right" | 71
| 128,91810(3)
| 3,5(3)&nbsp;mnt
| β+
| 129La
| (5/2+)
|
|
|-
| 130Ce
| style="text-align:right" | 58
| style="text-align:right" | 72
| 129,91474(3)
| 22,9(5)&nbsp;mnt
| β+
| 130La
| 0+
|
|
|-
| style="text-indent:1em" | 130mCe
| colspan="3" style="text-indent:2em" | 2453,6(3)&nbsp;keV
| 100(8)&nbsp;ndtk
|
|
| (7−)
|
|
|-
| 131Ce
| style="text-align:right" | 58
| style="text-align:right" | 73
| 130,91442(4)
| 10,2(3)&nbsp;mnt
| β+
| 131La
| (7/2+)
|
|
|-
| style="text-indent:1em" | 131mCe
| colspan="3" style="text-indent:2em" | 61,8(1)&nbsp;keV
| 5,0(10)&nbsp;mnt
| β+
| 131La
| (1/2+)
|
|
|-
| 132Ce
| style="text-align:right" | 58
| style="text-align:right" | 74
| 131,911460(22)
| 3,51(11)&nbsp;jam
| β+
| 132La
| 0+
|
|
|-
| style="text-indent:1em" | 132mCe
| colspan="3" style="text-indent:2em" | 2340,8(5)&nbsp;keV
| 9,4(3)&nbsp;ms
| IT
| 132Ce
| (8−)
|
|
|-
| 133Ce
| style="text-align:right" | 58
| style="text-align:right" | 75
| 132,911515(18)
| 97(4)&nbsp;mnt
| β+
| 133La
| 1/2+
|
|
|-
| style="text-indent:1em" | 133mCe
| colspan="3" style="text-indent:2em" | 37,1(8)&nbsp;keV
| 4,9(4)&nbsp;hri
| β+
| 133La
| 9/2−
|
|
|-
| 134Ce
| style="text-align:right" | 58
| style="text-align:right" | 76
| 133,908925(22)
| 3,16(4)&nbsp;hri
| EC
| 134La
| 0+
|
|
|-
| 135Ce
| style="text-align:right" | 58
| style="text-align:right" | 77
| 134,909151(12)
| 17,7(3)&nbsp;jam
| β+
| 135La
| 1/2(+)
|
|
|-
| style="text-indent:1em" | 135mCe
| colspan="3" style="text-indent:2em" | 445,8(2)&nbsp;keV
| 20(1)&nbsp;dtk
| IT
| 135Ce
| (11/2−)
|
|
|-
| 136Ce
| style="text-align:right" | 58
| style="text-align:right" | 78
| 135,907172(14)
| colspan=3 align=center|**[[Stabil Secara Pengamatan]]**
| 0+
| 0,00185(2)
| 0,00185–0,00186
|-
| style="text-indent:1em" | 136mCe
| colspan="3" style="text-indent:2em" | 3095,5(4)&nbsp;keV
| 2,2(2)&nbsp;µdtk
|
|
| 10+
|
|
|-
| 137Ce
| style="text-align:right" | 58
| style="text-align:right" | 79
| 136,907806(14)
| 9,0(3)&nbsp;jam
| β+
| 137La
| 3/2+
|
|
|-
| rowspan=2 style="text-indent:1em" | 137mCe
| rowspan=2 colspan="3" style="text-indent:2em" | 254,29(5)&nbsp;keV
| rowspan=2|34,4(3)&nbsp;jam
| IT (99,22%)
| 137Ce
| rowspan=2|11/2−
| rowspan=2|
| rowspan=2|
|-
| β+ (0,779%)
| 137La
|-
| 138Ce
| style="text-align:right" | 58
| style="text-align:right" | 80
| 137,905991(11)
| colspan=3 align=center|**Stabil Secara Pengamatan**
| 0+
| 0,00251(2)
| 0,00251–0,00254
|-
| style="text-indent:1em" | 138mCe
| colspan="3" style="text-indent:2em" | 2129,17(12)&nbsp;keV
| 8,65(20)&nbsp;mdtk
| IT
| **<sup>138</sup>Ce**
| 7-
|
|
|-
| 139Ce
| style="text-align:right" | 58
| style="text-align:right" | 81
| 138,906653(8)
| 137,641(20)&nbsp;hri
| EC
| **<sup>139</sup>La**
| 3/2+
|
|
|-
| style="text-indent:1em" | 139mCe
| colspan="3" style="text-indent:2em" | 754,24(8)&nbsp;keV
| 56,54(13)&nbsp;dtk
| IT
| 139Ce
| 11/2−
|
|
|-
| 140Ce
| style="text-align:right" | 58
| style="text-align:right" | 82
| 139,9054387(26)
| colspan=3 align=center|**Stabil**
| 0+
| 0,88450(51)
| 0,88446–0,88449
|-
| style="text-indent:1em" | 140mCe
| colspan="3" style="text-indent:2em" | 2107,85(3)&nbsp;keV
| 7,3(15)&nbsp;µdtk
|
|
| 6+
|
|
|-
| 141Ce
| style="text-align:right" | 58
| style="text-align:right" | 83
| 140,9082763(26)
| 32,508(13)&nbsp;hri
| β−
| **<sup>141</sup>Pr**
| 7/2−
|
|
|-
| 142Ce
| style="text-align:right" | 58
| style="text-align:right" | 84
| 141,909244(3)
| colspan=3 align=center|**Stabil Secara Pengamatan**
| 0+
| 0,11114(51)
| 0,11114–0,11114
|-
| 143Ce
| style="text-align:right" | 58
| style="text-align:right" | 85
| 142,912386(3)
| 33,039(6)&nbsp;jam
| β−
| 143Pr
| 3/2−
|
|
|-
| 144Ce
| style="text-align:right" | 58
| style="text-align:right" | 86
| 143,913647(4)
| 284,91(5)&nbsp;hri
| β−
| 144mPr
| 0+
|
|
|-
| 145Ce
| style="text-align:right" | 58
| style="text-align:right" | 87
| 144,91723(4)
| 3,01(6)&nbsp;mnt
| β−
| 145Pr
| (3/2−)
|
|
|-
| 146Ce
| style="text-align:right" | 58
| style="text-align:right" | 88
| 145,91876(7)
| 13,52(13)&nbsp;mnt
| β−
| 146Pr
| 0+
|
|
|-
| 147Ce
| style="text-align:right" | 58
| style="text-align:right" | 89
| 146,92267(3)
| 56,4(10)&nbsp;dtk
| β−
| 147Pr
| (5/2−)
|
|
|-
| 148Ce
| style="text-align:right" | 58
| style="text-align:right" | 90
| 147,92443(3)
| 56(1)&nbsp;dtk
| β−
| 148Pr
| 0+
|
|
|-
| 149Ce
| style="text-align:right" | 58
| style="text-align:right" | 91
| 148,9284(1)
| 5,3(2)&nbsp;dtk
| β−
| 149Pr
| (3/2−)#
|
|
|-
| 150Ce
| style="text-align:right" | 58
| style="text-align:right" | 92
| 149,93041(5)
| 4,0(6)&nbsp;dtk
| β−
| 150Pr
| 0+
|
|
|-
| 151Ce
| style="text-align:right" | 58
| style="text-align:right" | 93
| 150,93398(11)
| 1,02(6)&nbsp;dtk
| β−
| 151Pr
| 3/2−#
|
|
|-
| 152Ce
| style="text-align:right" | 58
| style="text-align:right" | 94
| 151,93654(21)#
| 1,4(2)&nbsp;dtk
| β−
| 152Pr
| 0+
|
|
|-
| 153Ce
| style="text-align:right" | 58
| style="text-align:right" | 95
| 152,94058(43)#
| 500#&nbsp;mdtk [>300&nbsp;ndtk]
| β−
| 153Pr
| 3/2−#
|
|
|-
| 154Ce
| style="text-align:right" | 58
| style="text-align:right" | 96
| 153.94342(54)#
| 300#&nbsp;mdtk [>300&nbsp;ndtk]
| β−
| 154Pr
| 0+
|
|
|-
| 155Ce
| style="text-align:right" | 58
| style="text-align:right" | 97
| 154,94804(64)#
| 200#&nbsp;mdtk [>300&nbsp;ndtk]
| β−
| 155Pr
| 5/2−#
|
|
|-
| 156Ce
| style="text-align:right" | 58
| style="text-align:right" | 98
| 155,95126(64)#
| 150#&nbsp;mdtk
| β−
| 156Pr
| 0+
|
|
|-
| 157Ce
| style="text-align:right" | 58
| style="text-align:right" | 99
| 156,95634(75)#
| 50#&nbsp;mdtk
| β−
| 157Pr
| 7/2+#
|
|

## Referensi

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