Isotopes of krypton

There are 34 known isotopes of krypton (₃₆Kr) with atomic mass numbers from 67 to 103. Naturally occurring krypton is made of five stable isotopes and one ({{SimpleNuclide|krypton|78}}) which is slightly radioactive with an extremely long half-life, plus traces of radioisotopes that are produced by cosmic rays in the atmosphere.

List of isotopes

{{Isotopes table

| symbol = Kr

| refs = NUBASE2020, AME2020 II

| notes = m, unc(), mass#, hl#, hl-nst, spin(), spin#, daughter-st, daughter-nst, n

}}

|-id=Krypton-67

| rowspan=2|⁶⁷Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 31

| rowspan=2|66.98331(46)#

| rowspan=2|7.4(29) ms

| β⁺? (63%)

| ⁶⁷Br

| rowspan=2|3/2-#

| rowspan=2|

|2p (37%)

|⁶⁵Se

|-id=Krypton-68

| rowspan=3|⁶⁸Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 32

| rowspan=3|67.97249(54)#

| rowspan=3|21.6(33) ms

| β⁺, p (>90%)

| ⁶⁷Se

| rowspan=3|0+

| rowspan=3|

|β⁺? (<10%)

|⁶⁸Br

|p?

|⁶⁷Br

|-id=Krypton-69

| rowspan=2|⁶⁹Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 33

| rowspan=2|68.96550(32)#

| rowspan=2|27.9(8) ms

| β⁺, p (94%)

| ⁶⁸Se

| rowspan=2|(5/2−)

| rowspan=2|

| β⁺ (6%)

| ⁶⁹Br

|-id=Krypton-70

| rowspan=2|⁷⁰Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 34

| rowspan=2|69.95588(22)#

| rowspan=2|45.00(14) ms

| β⁺ (>98.7%)

| ⁷⁰Br

| rowspan=2|0+

| rowspan=2|

| β⁺, p (<1.3%)

| ⁶⁹Se

|-id=Krypton-71

| rowspan=2|⁷¹Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 35

| rowspan=2|70.95027(14)

| rowspan=2|98.8(3) ms

| β⁺ (97.9%)

| ⁷¹Br

| rowspan=2|(5/2)−

| rowspan=2|

| β⁺, p (2.1%)

| ⁷⁰Se

|-id=Krypton-72

| ⁷²Kr

| style="text-align:right" | 36

| 71.9420924(86)

| 17.16(18) s

| β⁺

| ⁷²Br

| 0+

|-id=Krypton-73

| rowspan=2|⁷³Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 37

| rowspan=2|72.9392892(71)

| rowspan=2|27.3(10) s

| β⁺ (99.75%)

| ⁷³Br

| rowspan=2|(3/2)−

| rowspan=2|

| β⁺, p (0.25%)

| ⁷²Se

|-id=Krypton-73m

| style="text-indent:1em" | ^73mKr

| colspan="3" style="text-indent:2em" | 433.55(13) keV

| 107(10) ns

| IT

| ⁷³Kr

| (9/2+)

|-id=Krypton-74

| ⁷⁴Kr

| style="text-align:right" | 36

| style="text-align:right" | 38

| 73.9330840(22)

| 11.50(11) min

| β⁺

| ⁷⁴Br

| 0+

|-id=Krypton-75

| ⁷⁵Kr

| style="text-align:right" | 36

| style="text-align:right" | 39

| 74.9309457(87)

| 4.60(7) min

| β⁺

| ⁷⁵Br

| 5/2+

|-id=Krypton-76

| ⁷⁶Kr

| style="text-align:right" | 36

| style="text-align:right" | 40

| 75.9259107(43)

| 14.8(1) h

| β⁺

| ⁷⁶Br

| 0+

|-id=Krypton-77

| ⁷⁷Kr

| style="text-align:right" | 36

| style="text-align:right" | 41

| 76.9246700(21)

| 72.6(9) min

| β⁺

| ⁷⁷Br

| 5/2+

|-id=Krypton-77m

| style="text-indent:1em" | ^77mKr

| colspan="3" style="text-indent:2em" | 66.50(5) keV

| 118(12) ns

| IT

| ⁷⁷Kr

| 3/2−

|-id=Krypton-78

| ⁷⁸KrPrimordial radionuclide

| style="text-align:right" | 36

| style="text-align:right" | 42

| 77.92036634(33)

| align=center|9.2 {{±|5.5|2.6}} {{±|1.3}}{{e|21}} y

|Double EC

|⁷⁸Se

| 0+

| 0.00355(3)

|-id=Krypton-79

| ⁷⁹Kr

| style="text-align:right" | 36

| style="text-align:right" | 43

| 78.9200829(37)

| 35.04(10) h

| β⁺

| ⁷⁹Br

| 1/2−

|-id=Krypton-79m

| style="text-indent:1em" | ^79mKr

| colspan="3" style="text-indent:2em" | 129.77(5) keV

| 50(3) s

| IT

| ⁷⁹Kr

| 7/2+

|-id=Krypton-80

| ⁸⁰Kr

| style="text-align:right" | 36

| style="text-align:right" | 44

| 79.91637794(75)

| colspan=3 align=center|Stable

| 0+

| 0.02286(10)

| ⁸¹KrUsed to date groundwater

| style="text-align:right" | 36

| style="text-align:right" | 45

| 80.9165897(12)

| 2.29(11)×10⁵ y

| EC

| ⁸¹Br

| 7/2+

| {{val|6e-13}}{{cite journal |last1=Lu |first1=Zheng-Tian |title=What trapped atoms reveal about global groundwater |journal=Physics Today |date=1 March 2013 |volume=66 |issue=3 |pages=74–75 |doi=10.1063/PT.3.1926 |bibcode=2013PhT....66c..74L |url=https://pubs.aip.org/physicstoday/article/66/3/74/414350/What-trapped-atoms-reveal-about-global |access-date=29 June 2024}}

|-id=Krypton-81m

| rowspan=2 style="text-indent:1em" | ^81mKr

| rowspan=2 colspan="3" style="text-indent:2em" | 190.64(4) keV

| rowspan=2|13.10(3) s

| IT

| ⁸¹Kr

| rowspan=2|1/2−

| rowspan=2|

| EC (0.0025%)

| ⁸¹Br

|-id=Krypton-82

| ⁸²Kr

| style="text-align:right" | 36

| style="text-align:right" | 46

| 81.9134811537(59)

| colspan=3 align=center|Stable

| 0+

| 0.11593(31)

|-id=Krypton-83

| ⁸³KrFission product

| style="text-align:right" | 36

| style="text-align:right" | 47

| 82.914126516(9)

| colspan=3 align=center|Stable

| 9/2+

| 0.11500(19)

|-id=Krypton-83m1

| style="text-indent:1em" | ^83m1Kr

| colspan="3" style="text-indent:2em" | 9.4053(8) keV

| 156.8(5) ns

| IT

| ⁸³Kr

| 7/2+

|-id=Krypton-83m2

| style="text-indent:1em" | ^83m2Kr

| colspan="3" style="text-indent:2em" | 41.5575(7) keV

| 1.830(13) h

| IT

| ⁸³Kr

| 1/2−

|-id=Krypton-84

| ⁸⁴Kr

| style="text-align:right" | 36

| style="text-align:right" | 48

| 83.9114977271(41)

| colspan=3 align=center|Stable

| 0+

| 0.56987(15)

|-id=Krypton-84m

| style="text-indent:1em" | ^84mKr

| colspan="3" style="text-indent:2em" | 3236.07(18) keV

| 1.83(4) μs

| IT

| ⁸⁴Kr

| 8+

| ⁸⁵Kr

| style="text-align:right" | 36

| style="text-align:right" | 49

| 84.9125273(21)

| 10.728(7) y

| β⁻

| ⁸⁵Rb

| 9/2+

| {{val|1e-11}}

|-id=Krypton-85m1

| rowspan=2 style="text-indent:1em" | ^85m1Kr

| rowspan=2 colspan="3" style="text-indent:2em" | 304.871(20) keV

| rowspan=2|4.480(8) h

| β⁻ (78.8%)

| ⁸⁵Rb

| rowspan=2|1/2−

| rowspan=2|

| IT (21.2%)

| ⁸⁵Kr

|-id=Krypton-85m2

| style="text-indent:1em" | ^85m2Kr

| colspan="3" style="text-indent:2em" | 1991.8(2) keV

| 1.82(5) μs

| IT

| ⁸⁵Kr

| (17/2+)

| ⁸⁶KrFormerly used to define the meter

| style="text-align:right" | 36

| style="text-align:right" | 50

| 85.9106106247(40)

| colspan=3 align=center|Observationally StableBelieved to decay by β⁻β⁻ to ⁸⁶Sr

| 0+

| 0.17279(41)

|-id=Krypton-87

| ⁸⁷Kr

| style="text-align:right" | 36

| style="text-align:right" | 51

| 86.91335476(26)

| 76.3(5) min

| β⁻

| ⁸⁷Rb

| 5/2+

|-id=Krypton-88

| ⁸⁸Kr

| style="text-align:right" | 36

| style="text-align:right" | 52

| 87.9144479(28)

| 2.825(19) h

| β⁻

| ⁸⁸Rb

| 0+

|-id=Krypton-89

| ⁸⁹Kr

| style="text-align:right" | 36

| style="text-align:right" | 53

| 88.9178354(23)

| 3.15(4) min

| β⁻

| ⁸⁹Rb

| 3/2+

|-id=Krypton-90

| ⁹⁰Kr

| style="text-align:right" | 36

| style="text-align:right" | 54

| 89.9195279(20)

| 32.32(9) s

| β⁻

| ^90mRb

| 0+

|-id=Krypton-91

| rowspan=2|⁹¹Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 55

| rowspan=2|90.9238063(24)

| rowspan=2|8.57(4) s

| β⁻

| ⁹¹Rb

| rowspan=2|5/2+

| rowspan=2|

| β⁻, n?

| ⁹⁰Rb

|-id=Krypton-92

| rowspan=2|⁹²Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 56

| rowspan=2|91.9261731(29)

| rowspan=2|1.840(8) s

| β⁻ (99.97%)

| ⁹²Rb

| rowspan=2|0+

| rowspan=2|

| β⁻, n (0.0332%)

| ⁹¹Rb

|-id=Krypton-93

| rowspan=2|⁹³Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 57

| rowspan=2|92.9311472(27)

| rowspan=2|1.287(10) s

| β⁻ (98.05%)

| ⁹³Rb

| rowspan=2|1/2+

| rowspan=2|

| β⁻, n (1.95%)

| ⁹²Rb

|-id=Krypton-94

| rowspan=2|⁹⁴Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 58

| rowspan=2|93.934140(13)

| rowspan=2|212(4) ms

| β⁻ (98.89%)

| ⁹⁴Rb

| rowspan=2|0+

| rowspan=2|

| β⁻, n (1.11%)

| ⁹³Rb

|-id=Krypton-95

| rowspan=3|⁹⁵Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 59

| rowspan=3|94.939711(20)

| rowspan=3|114(3) ms

| β⁻ (97.13%)

| ⁹⁵Rb

| rowspan=3|1/2+

| rowspan=3|

| β⁻, n (2.87%)

| ⁹⁴Rb

| β⁻, 2n?

| ⁹³Rb

|-id=Krypton-95m

| style="text-indent:1em" | ^95mKr

| colspan="3" style="text-indent:2em" | 195.5(3) keV

| 1.582(22) μs

| IT

| ⁹⁵Kr

| (7/2+)

|-id=Krypton-96

| rowspan=2|⁹⁶Kr

| rowspan=2 style="text-align:right" | 36

| rowspan=2 style="text-align:right" | 60

| rowspan=2|95.942998(62){{Cite journal|url=https://link.springer.com/article/10.1007/s10751-020-01722-2|doi = 10.1007/s10751-020-01722-2|title = High-precision mass measurement of neutron-rich 96Kr|year = 2020|last1 = Smith|first1 = Matthew B.|last2 = Murböck|first2 = Tobias|last3 = Dunling|first3 = Eleanor|last4 = Jacobs|first4 = Andrew|last5 = Kootte|first5 = Brian|last6 = Lan|first6 = Yang|last7 = Leistenschneider|first7 = Erich|last8 = Lunney|first8 = David|last9 = Lykiardopoulou|first9 = Eleni Marina|last10 = Mukul|first10 = Ish|last11 = Paul|first11 = Stefan F.|last12 = Reiter|first12 = Moritz P.|last13 = Will|first13 = Christian|last14 = Dilling|first14 = Jens|last15 = Kwiatkowski|first15 = Anna A.|journal = Hyperfine Interactions|volume = 241| issue=1 | page=59 | bibcode=2020HyInt.241...59S |s2cid = 220512482}}

| rowspan=2|80(8) ms

| β⁻ (96.3%)

| ⁹⁶Rb

| rowspan=2|0+

| rowspan=2|

| β⁻, n (3.7%)

| ⁹⁵Rb

|-id=Krypton-97

| rowspan=3|⁹⁷Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 61

| rowspan=3|96.94909(14)

| rowspan=3|62.2(32) ms

| β⁻ (93.3%)

| ⁹⁷Rb

| rowspan=3|3/2+#

| rowspan=3|

| β⁻, n (6.7%)

| ⁹⁶Rb

| β⁻, 2n?

| ⁹⁵Rb

|-id=Krypton-98

| rowspan=3|⁹⁸Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 62

| rowspan=3|97.95264(32)#

| rowspan=3|42.8(36) ms

| β⁻ (93.0%)

| ⁹⁸Rb

| rowspan=3|0+

| rowspan=3|

| β⁻, n (7.0%)

| ⁹⁷Rb

| β⁻, 2n?

| ⁹⁶Rb

|-id=Krypton-99

| rowspan=3|⁹⁹Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 63

| rowspan=3|98.95878(43)#

| rowspan=3|40(11) ms

| β⁻ (89%)

| ⁹⁹Rb

| rowspan=3|5/2−#

| rowspan=3|

| β⁻, n (11%)

| ⁹⁸Rb

| β⁻, 2n?

| ⁹⁷Rb

|-id=Krypton-100

| rowspan=3|¹⁰⁰Kr

| rowspan=3 style="text-align:right" | 36

| rowspan=3 style="text-align:right" | 64

| rowspan=3|99.96300(43)#

| rowspan=3|12(8) ms

| β⁻

| ¹⁰⁰Rb

| rowspan=3|0+

| rowspan=3|

| β⁻, n?

| ⁹⁹Rb

| β⁻, 2n?

| ⁹⁸Rb

|-id=Krypton-101

| rowspan=3 | ¹⁰¹Kr

| rowspan=3 | 36

| rowspan=3 | 65

| rowspan=3 | 100.96932(54)#

| rowspan=3 | 9# ms
[>400 ns]

| β⁻?

| ¹⁰¹Rb

| rowspan=3 | 5/2+#

| rowspan=3 |

| β⁻, n?

| ¹⁰⁰Rb

| β⁻, 2n?

| ⁹⁹Rb

|-id=Krypton-102

| ¹⁰²Kr{{Cite journal|url=https://journals.aps.org/prc/abstract/10.1103/PhysRevC.103.014614|doi = 10.1103/PhysRevC.103.014614|title = Observation of new neutron-rich isotopes in the vicinity of Zr110|year = 2021|last1 = Sumikama|first1 = T.|last2 = Fukuda|first2 = N.|last3 = Inabe|first3 = N.|last4 = Kameda|first4 = D.|last5 = Kubo|first5 = T.|last6 = Shimizu|first6 = Y.|last7 = Suzuki|first7 = H.|last8 = Takeda|first8 = H.|last9 = Yoshida|first9 = K.|last10 = Baba|first10 = H.|last11 = Browne|first11 = F.|last12 = Bruce|first12 = A. M.|last13 = Carroll|first13 = R.|last14 = Chiga|first14 = N.|last15 = Daido|first15 = R.|last16 = Didierjean|first16 = F.|last17 = Doornenbal|first17 = P.|last18 = Fang|first18 = Y.|last19 = Gey|first19 = G.|last20 = Ideguchi|first20 = E.|last21 = Isobe|first21 = T.|last22 = Lalkovski|first22 = S.|last23 = Li|first23 = Z.|last24 = Lorusso|first24 = G.|last25 = Lozeva|first25 = R.|last26 = Nishibata|first26 = H.|last27 = Nishimura|first27 = S.|last28 = Nishizuka|first28 = I.|last29 = Odahara|first29 = A.|last30 = Patel|first30 = Z.|journal = Physical Review C|volume = 103| issue=1 | page=014614 | bibcode=2021PhRvC.103a4614S |s2cid = 234019083|display-authors = 1|hdl = 10261/260248|hdl-access = free}}

| style="text-align:right" | 36

| style="text-align:right" | 66

| 0+

|-id=Krypton-103

| ¹⁰³Kr{{cite journal |last1=Shimizu |first1=Y. |last2=Kubo |first2=T. |last3=Sumikama |first3=T. |last4=Fukuda |first4=N. |last5=Takeda |first5=H. |last6=Suzuki |first6=H. |last7=Ahn |first7=D. S. |last8=Inabe |first8=N. |last9=Kusaka |first9=K. |last10=Ohtake |first10=M. |last11=Yanagisawa |first11=Y. |last12=Yoshida |first12=K. |last13=Ichikawa |first13=Y. |last14=Isobe |first14=T. |last15=Otsu |first15=H. |last16=Sato |first16=H. |last17=Sonoda |first17=T. |last18=Murai |first18=D. |last19=Iwasa |first19=N. |last20=Imai |first20=N. |last21=Hirayama |first21=Y. |last22=Jeong |first22=S. C. |last23=Kimura |first23=S. |last24=Miyatake |first24=H. |last25=Mukai |first25=M. |last26=Kim |first26=D. G. |last27=Kim |first27=E. |last28=Yagi |first28=A. |title=Production of new neutron-rich isotopes near the N = 60 isotones Ge 92 and As 93 by in-flight fission of a 345 MeV/nucleon U 238 beam |journal=Physical Review C |date=8 April 2024 |volume=109 |issue=4 |page=044313 |doi=10.1103/PhysRevC.109.044313 }}

| style="text-align:right" | 36

| style="text-align:right" | 67

The isotopic composition refers to that in air.

Notable isotopes

= Krypton-81 =

{{Expand section|1=Usage in hydrogeology, ATC=V09|date=October 2019}}

Krypton-81 is useful in determining how old the water beneath the ground is.{{Cite journal |last=Le-Yi Tu, Guo-Min Yang, Cun-Feng Cheng, Gu-Liang Liu, Xiang-Yang Zhang, and Shui-Ming Hu |first= |date=2014 |title=Analysis of Krypton-85 and Krypton-81 in a Few Liters of Air |url= |journal=Analytical Chemistry |volume=86 |issue=8 |pages=4002-4007 |via=}} Radioactive krypton-81 is the product of spallation reactions with cosmic rays striking gases present in the Earth atmosphere, along with the six stable or nearly stable krypton isotopes.{{cite journal|last1=Leya|first1=I. |last2=Gilabert|first2=E. |last3=Lavielle|first3=B. |last4=Wiechert|first4=U. |last5=Wieler|first5=W. |date=2004 |title=Production rates for cosmogenic krypton and argon isotopes in H-chondrites with known ³⁶Cl-³⁶Ar ages |journal=Antarctic Meteorite Research |volume=17 |pages=185–199 |bibcode=2004AMR....17..185L |url=https://core.ac.uk/download/pdf/51485498.pdf}} Krypton-81 has a half-life of about 229,000 years.

Krypton-81 is used for dating ancient (50,000- to 800,000-year-old) groundwater and to determine their residence time in deep aquifers. One of the main technical limitations of the method is that it requires the sampling of very large volumes of water: several hundred liters or a few cubic meters of water. This is particularly challenging for dating pore water in deep clay aquitards with very low hydraulic conductivity.

{{cite report

|author=N. Thonnard |author2=L. D. MeKay |author3=T. C. Labotka

|year=2001

|title=Development of Laser-Based Resonance Ionization Techniques for 81-Kr and 85-Kr Measurements in the Geosciences

|url=https://digital.library.unt.edu/ark:/67531/metadc737461/m2/1/high_res_d/809813.pdf

|pages=4–7

|publisher=University of Tennessee, Institute for Rare Isotope Measurements

|doi=10.2172/809813 }}

= Krypton-85 =

Krypton-85 has a half-life of about 10.75 years. This isotope is produced by the nuclear fission of uranium and plutonium in nuclear weapons testing and in nuclear reactors, as well as by cosmic rays. An important goal of the Limited Nuclear Test Ban Treaty of 1963 was to eliminate the release of such radioisotopes into the atmosphere, and since 1963 much of that krypton-85 has had time to decay. However, it is almost inevitable that krypton-85 is released during the reprocessing of fuel rods from nuclear reactors.{{cite web | title=Environmental Consequences Of Atmospheric Krypton-85 | url=https://inis.iaea.org/collection/NCLCollectionStore/_Public/11/569/11569296.pdf | access-date=2024-12-08 | page=8 }}

== Atmospheric concentration ==

The atmospheric concentration of krypton-85 around the North Pole is about 30 percent higher than that at the Amundsen–Scott South Pole Station because nearly all of the world's nuclear reactors and all of its major nuclear reprocessing plants are located in the northern hemisphere, and also well-north of the equator.{{cite web

|title=Resources on Isotopes

|url=http://wwwrcamnl.wr.usgs.gov/isoig/period/kr_iig.html

|archive-url=https://web.archive.org/web/20010924204348/http://wwwrcamnl.wr.usgs.gov/isoig/period/kr_iig.html

|url-status=dead

|archive-date=2001-09-24

|publisher=U.S. Geological Survey

|access-date=2007-03-20

}}

To be more specific, those nuclear reprocessing plants with significant capacities are located in the United States, the United Kingdom, the French Republic, the Russian Federation, Mainland China (PRC), Japan, India, and Pakistan.

= Krypton-86 =

Krypton-86 was formerly used to define the meter from 1960 until 1983, when the definition of the meter was based on the wavelength of the 606 nm (orange) spectral line of a krypton-86 atom.{{cite journal | title=The International Length Standard | first1=K. M. | last1=Baird | first2=L. E. | last2=Howlett | journal=Applied Optics | volume=2 | issue=5 | pages=455–463 | year=1963 | doi=10.1364/AO.2.000455| bibcode=1963ApOpt...2..455B }}

= Others =

All other radioisotopes of krypton have half-lives of less than one day, except for krypton-79, a positron emitter with a half-life of about 35.0 hours.

References

= Sources =

Isotope masses from:
{{NUBASE 2003}}
Isotopic compositions and standard atomic masses from:
{{CIAAW2003}}
{{CIAAW 2005}}
Half-life, spin, and isomer data selected from the following sources.
{{NUBASE 2003}}
{{NNDC}}
{{CRC85|chapter=11}}

External links

[http://www.nndc.bnl.gov/chart/reCenter.jsp?z=36&n=65 Brookhaven National Laboratory: Krypton-101 information] {{Webarchive|url=https://web.archive.org/web/20171018072258/http://www.nndc.bnl.gov/chart/reCenter.jsp?z=36&n=65 |date=2017-10-18 }}

Category:Krypton

Krypton