Изотопи на селенот

**[[Селен|Селенот]]** (34 Se) има шест природни изотопи кои се појавуваат во значителни количини, заедно со расеаниот изотоп Se, кој се јавува во мали количини во рудите на ураниум. Пет од овие изотопи се стабилни: 74Se, 76Se, 77Se, 78Se и 80Se. Последните три се појавуваат и како производи за цепење, заедно со Se, кој има полураспад од 327.000 години,   и 82Se, кој има многу долг полураспад (~ 10 20 години, преку двојно бета распаѓање до <sup>82</sup>Kr ) и може да се смета за практични цели. Постојат 23 други нестабилни изотопи кои се карактеризирани, од кои најдолговечни се 79Se со полураспад од 327.000 години, 75Se со полураспад од 120 денови и 72Se со полураспад од 8,40 денови. Од другите изотопи, 73Se има најдолг полураспад, 7,15 часа; повеќето други имаат полураспад не подолг од 38 секунди.

## Список на изотопи

|-id=Selenium-63
| rowspan=3|63Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 29
| rowspan=3|62.98191(54)#
| rowspan=3|13.2(39)&nbsp;ms
| β<sup>+</sup>, п (89%)
| 62Ge
| rowspan=3|3/2−#
| rowspan=3|
| rowspan=3|
|-
| β+ (11%)
| 63As
|-
| 2p? (61Ge
|-id=Selenium-64
| rowspan=2|64Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 30
| rowspan=2|63.97117(54)#
| rowspan=2|22.6(2)&nbsp;ms
| β+?
| 64As
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β+, p?
| 63Ge
|-id=Selenium-65
| rowspan=2|65Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 31
| rowspan=2|64.96455(32)#
| rowspan=2|34.2(7)&nbsp;ms
| β+, p (87%)
| 64Ge
| rowspan=2|3/2−#
| rowspan=2|
| rowspan=2|
|-
| β+ (13%)
| 65As
|-id=Selenium-66
| rowspan=2|66Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 32
| rowspan=2|65.95528(22)#
| rowspan=2|54(4)&nbsp;ms
| β+
| 66As
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β+, p?
| 65Ge
|-id=Selenium-67
| rowspan=2|67Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 33
| rowspan=2|66.949994(72)
| rowspan=2|133(4)&nbsp;ms
| β+ (99.5%)
| 67As
| rowspan=2|5/2−#
| rowspan=2|
| rowspan=2|
|-
| β+, p (0.5%)
| 66Ge
|-id=Selenium-68
| 68Se
| style="text-align:right" | 34
| style="text-align:right" | 34
| 67.94182524(53)
| 35.5(7)&nbsp;s
| β+
| 68As
| 0+
|
|
|-id=Selenium-69
| rowspan=2|69Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 35
| rowspan=2|68.9394148(16)
| rowspan=2|27.4(2)&nbsp;s
| β+ (99.95%)
| 69As
| rowspan=2|1/2−
| rowspan=2|
| rowspan=2|
|-
| β+, p (.052%)
| 68Ge
|-id=Selenium-69m1
| style="text-indent:1em" | 69m1Se
| colspan="3" style="text-indent:2em" | 38.85(22)&nbsp;keV
| 2.0(2)&nbsp;μs
| ИП
| 69Se
| 5/2−
|
|
|-id=Selenium-69m2
| style="text-indent:1em" | 69m2Se
| colspan="3" style="text-indent:2em" | 574.0(4)&nbsp;keV
| 955(16)&nbsp;ns
| ИП
| 69Se
| 9/2+
|
|
|-id=Selenium-70
| 70Se
| style="text-align:right" | 34
| style="text-align:right" | 36
| 69.9335155(17)
| 41.1(3)&nbsp;min
| β+
| 70As
| 0+
|
|
|-id=Selenium-71
| 71Se
| style="text-align:right" | 34
| style="text-align:right" | 37
| 70.9322094(30)
| 4.74(5)&nbsp;min
| β+
| 71As
| (5/2−)
|
|
|-id=Selenium-71m1
| style="text-indent:1em" | 71m1Se
| colspan="3" style="text-indent:2em" | 48.79(5)&nbsp;keV
| 5.6(7)&nbsp;μs
| ИП
| 71Se
| (1/2−)
|
|
|-id=Selenium-71m2
| style="text-indent:1em" | 71m2Se
| colspan="3" style="text-indent:2em" | 260.48(10)&nbsp;keV
| 19.0(5)&nbsp;μs
| ИП
| 71Se
| (9/2+)
|
|
|-id=Selenium-72
| 72Se
| style="text-align:right" | 34
| style="text-align:right" | 38
| 71.9271405(21)
| 8.40(8)&nbsp;d
| ЕЗ
| 72As
| 0+
|
|
|-id=Selenium-73
| 73Se
| style="text-align:right" | 34
| style="text-align:right" | 39
| 72.9267549(80)
| 7.15(9)&nbsp;h
| β+
| 73As
| 9/2+
|
|
|-id=Selenium-73m
| rowspan=2 style="text-indent:1em" | 73mSe
| rowspan=2 colspan="3" style="text-indent:2em" | 25.71(4)&nbsp;keV
| rowspan=2|39.8(17)&nbsp;min
| ИП (72.6%)
| 73Se
| rowspan=2|3/2−
| rowspan=2|
| rowspan=2|
|-
| β+ (27.4%)
| 73As
|-id=Selenium-74
| 74Se
| style="text-align:right" | 34
| style="text-align:right" | 40
| 73.922475933(15)
| colspan=3 align=center|**[[Набљудувачко стабилен]]**
| 0+
| 0.0086(3)
|
|-id=Selenium-75
| 75Se
| style="text-align:right" | 34
| style="text-align:right" | 41
| 74.922522870(78)
| 119.78(3)&nbsp;d
| EC
| **<sup>75</sup>As**
| 5/2+
|
|
|-id=Selenium-76
| 76Se
| style="text-align:right" | 34
| style="text-align:right" | 42
| 75.919213702(17)
| colspan=3 align=center|**Стабилен**
| 0+
| 0.0923(7)
|
|-id=Selenium-77
| 77Se
| style="text-align:right" | 34
| style="text-align:right" | 43
| 76.919914150(67)
| colspan=3 align=center|**Стабилен**
| 1/2−
| 0.0760(7)
|
|-id=Selenium-77m
| style="text-indent:1em" | 77mSe
| colspan="3" style="text-indent:2em" | 161.9223(10)&nbsp;keV
| 17.36(5)&nbsp;s
| ИП
| **<sup>77</sup>Se**
| 7/2+
|
|
|-id=Selenium-78
| 78Se
| style="text-align:right" | 34
| style="text-align:right" | 44
| 77.91730924(19)
| colspan=3 align=center|**Стабилен**
| 0+
| 0.2369 (22)
|
|-
| <sup>79</sup>Se
| style="text-align:right" | 34
| style="text-align:right" | 45
| 78.91849925(24)
| 3.27(28)×105&nbsp;y
| β−
| **<sup>79</sup>Br**
| 7/2+
|
|
|-id=Selenium-79m
| rowspan=2 style="text-indent:1em" | 79mSe
| rowspan=2 colspan="3" style="text-indent:2em" | 95.77(3)&nbsp;keV
| rowspan=2|3.900(18)&nbsp;min
| ИП (99.94%)
| 79Se
| rowspan=2|1/2−
| rowspan=2|
| rowspan=2|
|-
| β− (0.056%)
| **<sup>79</sup>Br**
|-id=Selenium-80
| 80Se
| style="text-align:right" | 34
| style="text-align:right" | 46
| 79.9165218(10)
| colspan=3 align=center|**Набљудувачко стабилен**
| 0+
| 0.4980(36)
|
|-id=Selenium-81
| 81Se
| style="text-align:right" | 34
| style="text-align:right" | 47
| 80.9179930(10)
| 18.45(12)&nbsp;min
| β−
| **<sup>81</sup>Br**
| 1/2−
|
|
|-id=Selenium-81m
| rowspan=2 style="text-indent:1em" | 81mSe
| rowspan=2 colspan="3" style="text-indent:2em" | 103.00(6)&nbsp;keV
| rowspan=2|57.28(2)&nbsp;min
| ИП (99.95%)
| 81Se
| rowspan=2|7/2+
| rowspan=2|
| rowspan=2|
|-
| β− (.051%)
| **<sup>81</sup>Br**
|-id=Selenium-82
| 82Se
| style="text-align:right" | 34
| style="text-align:right" | 48
| 81.91669953(50)
| **8.76(15)×10<sup>19</sup> y**
| β<sup>−</sup>β<sup>−</sup>
| **<sup>82</sup>Kr**
| 0+
| 0.0882(15)
| 
|-id=Selenium-83
| 83Se
| style="text-align:right" | 34
| style="text-align:right" | 49
| 82.9191186(33)
| 22.25(4)&nbsp;min
| β−
| 83Br
| 9/2+
|
|
|-id=Selenium-83m
| style="text-indent:1em" | 83mSe
| colspan="3" style="text-indent:2em" | 228.92(7)&nbsp;keV
| 70.1(4)&nbsp;s
| β−
| 83Br
| 1/2−
|
|
|-id=Selenium-84
| 84Se
| style="text-align:right" | 34
| style="text-align:right" | 50
| 83.9184668(21)
| 3.26(10)&nbsp;min
| β−
| 84Br
| 0+
|
|
|-id=Selenium-85
| 85Se
| style="text-align:right" | 34
| style="text-align:right" | 51
| 84.9222608(28)
| 32.9(3)&nbsp;s
| β−
| 85Br
| (5/2)+
|
|
|-id=Selenium-86
| rowspan=2|86Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 52
| rowspan=2|85.9243117(27)
| rowspan=2|14.3(3)&nbsp;s
| β−
| 86Br
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β−, н?
| 85Br
|-id=Selenium-87
| rowspan=2|87Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 53
| rowspan=2|86.9286886(24)
| rowspan=2|5.50(6)&nbsp;s
| β− (99.50%)
| 87Br
| rowspan=2|(3/2+)
| rowspan=2|
| rowspan=2|
|-
| β−, n (0.60%)
| 86Br
|-id=Selenium-88
| rowspan=2|88Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 54
| rowspan=2|87.9314175(36)
| rowspan=2|1.53(6)&nbsp;s
| β− (99.01%)
| 88Br
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β−, n (0.99%)
| 87Br
|-id=Selenium-89
| rowspan=2|89Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 55
| rowspan=2|88.9366691(40)
| rowspan=2|430(50)&nbsp;ms
| β− (92.2%)
| 89Br
| rowspan=2|5/2+#
| rowspan=2|
| rowspan=2|
|-
| β−, n (7.8%)
| 88Br
|-id=Selenium-90
| rowspan=2|90Se
| rowspan=2 style="text-align:right" | 34
| rowspan=2 style="text-align:right" | 56
| rowspan=2|89.94010(35)
| rowspan=2|210(80)&nbsp;ms
| β−
| 90Br
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β−, n?
| 89Br
|-id=Selenium-91
| rowspan=3|91Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 57
| rowspan=3|90.94570(47)
| rowspan=3|270(50)&nbsp;ms
| β− (79%)
| 91Br
| rowspan=3|1/2+#
| rowspan=3|
| rowspan=3|
|-
| β−, n (21%)
| 90Br
|-
| β−, 2n?
| 89Br
|-id=Selenium-92
| rowspan=3|92Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 58
| rowspan=3|91.94984(43)#
| rowspan=3|90#&nbsp;ms [>300&nbsp;ns]
| β−?
| 92Br
| rowspan=3|0+
| rowspan=3|
| rowspan=3|
|-
| β−, n?
| 91Br
|-
| β−, 2n?
| 90Br
|-id=Selenium-92m
| style="text-indent:1em" | 92mSe
| colspan="3" style="text-indent:2em" | 3072(2)&nbsp;keV
| 15.7(7)&nbsp;μs
| ИП
| 92Se
| (9−)
|
|
|-id=Selenium-93
| rowspan=3|93Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 59
| rowspan=3|92.95614(43)#
| rowspan=3|130#&nbsp;ms [>300&nbsp;ns]
| β−?
| 93Br
| rowspan=3|1/2+#
| rowspan=3|
| rowspan=3|
|-
| β−, n?
| 92Br
|-
| β−, 2n?
| 91Br
|-id=Selenium-93m
| style="text-indent:1em" | 93mSe
| colspan="3" style="text-indent:2em" | 678.2(7)&nbsp;keV
| 420(100)&nbsp;ns
| ИП
| 93Se
| 
|
|
|-id=Selenium-94
| rowspan=3|94Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 60
| rowspan=3|93.96049(54)#
| rowspan=3|50#&nbsp;ms [>300&nbsp;ns]
| β−?
| 94Br
| rowspan=3|0+
| rowspan=3|
| rowspan=3|
|-
| β−, n?
| 93Br
|-
| β−, 2n?
| 92Br
|-id=Selenium-94m
| style="text-indent:1em" | 94mSe
| colspan="3" style="text-indent:2em" | 2430.0(6)&nbsp;keV
| 680(50)&nbsp;ns
| ИП
| 94Se
| (7−)
|
|
|-id=Selenium-95
| rowspan=3|95Se
| rowspan=3 style="text-align:right" | 34
| rowspan=3 style="text-align:right" | 61
| rowspan=3|94.96730(54)#
| rowspan=3|70#&nbsp;ms [>400&nbsp;ns]
| β−?
| 95Br
| rowspan=3|3/2+#
| rowspan=3|
| rowspan=3|
|-
| β−, n?
| 94Br
|-
| β−, 2n?
| 93Br
|-id=Selenium-96
| 96Se
| style="text-align:right" | 34
| style="text-align:right" | 62
| 
| 
| 
| 
|
|
|
|-id=Selenium-97
| 97Se
| style="text-align:right" | 34
| style="text-align:right" | 63
| 
| 
| 
| 
|
|
|

## Употреба на радиоизотопи
Изотопот селен-75 има радиофармацевтска употреба. На пример, се употребува во ендоректална брахитерапија со високи дози, како алтернатива на иридиум-192. 

Во палеобиогеохемијата, односот во количината на селен-82 до селен-76 (т.е. вредноста на δ82/76Se) може да се употреби за следење на редокс-условите на Земјата за време на неопротерозојскиот период со цел да се добие подлабоко разбирање за брзата оксигенација што предизвикува комплексна појава на организмот.  

## Белешки


## Наводи

селен
Категорија:селен