Isotopes of cadmium#Cadmium-106

Naturally occurring cadmium (₄₈Cd) is composed of 8 isotopes. For two of them, natural radioactivity was observed, and three others are predicted to be radioactive but their decays have not been observed, due to extremely long half-lives. The two natural radioactive isotopes are ¹¹³Cd (beta decay, half-life is 8.04 × 10¹⁵ years) and ¹¹⁶Cd (two-neutrino double beta decay, half-life is 2.8 × 10¹⁹ years). The other three are ¹⁰⁶Cd, ¹⁰⁸Cd (double electron capture), and ¹¹⁴Cd (double beta decay); only lower limits on their half-life times have been set. Three isotopes—¹¹⁰Cd, ¹¹¹Cd, and ¹¹²Cd—are theoretically stable. Among the isotopes absent in natural cadmium, the most long-lived are ¹⁰⁹Cd with a half-life of 462.6 days, and ¹¹⁵Cd with a half-life of 53.46 hours. All of the remaining radioactive isotopes have half-lives that are less than 2.5 hours and the majority of these have half-lives that are less than 5 minutes. This element also has 12 known meta states, with the most stable being ^113mCd (t_1/2 14.1 years), ^115mCd (t_1/2 44.6 days) and ^117mCd (t_1/2 3.36 hours).

The known isotopes of cadmium range in atomic mass from 94.950 u (⁹⁵Cd) to 131.946 u (¹³²Cd). The primary decay mode before the second most abundant stable isotope, ¹¹²Cd, is electron capture and the primary modes after are beta emission and electron capture. The primary decay product before ¹¹²Cd is element 47 (silver) and the primary product after is element 49 (indium).

A 2021 study has shown at high ionic strengths, Cd isotope fractionation mainly depends on its complexation with carboxylic sites. At low ionic strengths, nonspecific Cd binding induced by electrostatic attractions plays a dominant role and promotes Cd isotope fractionation during complexation.{{Cite journal|last1=Ratié|first1=Gildas|last2=Chrastný|first2=Vladislav|last3=Guinoiseau|first3=Damien|last4=Marsac|first4=Rémi|last5=Vaňková|first5=Zuzana|last6=Komárek|first6=Michael|date=2021-06-01|title=Cadmium Isotope Fractionation during Complexation with Humic Acid|url=https://doi.org/10.1021/acs.est.1c00646|journal=Environmental Science & Technology|volume=55|issue=11|pages=7430–7444|doi=10.1021/acs.est.1c00646|pmid=33970606 |bibcode=2021EnST...55.7430R |s2cid=234361430 |issn=0013-936X}}

List of isotopes

{{Isotopes table

| symbol = Cd

| refs = NUBASE2020, AME2020 II

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

}}

|-id=Cadmium-94

| ⁹⁴Cd

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

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

| 93.95659(54)#

| 80# ms
[>760 ns]

| 0+

|-id=Cadmium-95

| rowspan=2|⁹⁵Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 47

| rowspan=2|94.94948(61)#

| rowspan=2|32(3) ms

| β⁺ (95.4%)

| ⁹⁵Ag

| rowspan=2|9/2+#

| rowspan=2|

| β⁺, p (4.6%)

| ⁹⁴Pd

|-id=Cadmium-96

| rowspan=2|⁹⁶Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2|95.94034(44)#

| rowspan=2|1.003(47) s

| β⁺ (98.4%)

| ⁹⁶Ag

| rowspan=2|0+

| rowspan=2|

| β⁺, p (1.6%)

| ⁹⁵Pd

|-id=Cadmium-96m1

| rowspan=2 style="text-indent:1em" | ^96m1Cd

| rowspan=2 colspan="3" style="text-indent:2em" | 6000(1400) keV

| rowspan=2|511(26) ms

| β⁺ (84.6%)

| ⁹⁶Ag

| rowspan=2|16+

| rowspan=2|

| β⁺, p (15.4%)

| ⁹⁵Pd

|-id=Cadmium-96m2

| style="text-indent:1em" | ^96m2Cd

| colspan="3" style="text-indent:2em" | 5605(5) keV

| 198(18) ns

| IT

| ⁹⁶Cd

| (12−,13−)

|-id=Cadmium-97

| rowspan=2|⁹⁷Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 49

| rowspan=2|96.93480(45)

| rowspan=2|1.16(5) s

| β⁺ (92.6%)

| ⁹⁷Ag

| rowspan=2|(9/2+)

| rowspan=2|

| β⁺, p (7.4%)

| ⁹⁶Pd

|-id=Cadmium-97m1

| style="text-indent:1em" | ^97m1Cd

| colspan="3" style="text-indent:2em" | 1245.1(2) keV

| 730(70) μs

| IT

| ⁹⁷Cd

| (1/2−)

|-id=Cadmium-97m2

| rowspan=2 style="text-indent:1em" | ^97m2Cd

| rowspan=2 colspan="3" style="text-indent:2em" | 2620(580) keV

| rowspan=2|3.86(6) s

| β⁺ (74.9%)

| ⁹⁷Ag

| rowspan=2|(25/2+)

| rowspan=2|

| β⁺, p (25.1%)

| ⁹⁶Pd

|-id=Cadmium-98

| rowspan=2|⁹⁸Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 50

| rowspan=2|97.927389(56)

| rowspan=2|9.29(10) s

| β⁺ (>99.97%)

| ⁹⁸Ag

| rowspan=2|0+

| rowspan=2|

| β⁺, p (<0.029%)

| ⁹⁷Pd

|-id=Cadmium-98m1

| style="text-indent:1em" | ^98m1Cd

| colspan="3" style="text-indent:2em" | 2428.3(4) keV

| 154(16) ns

| IT

| ⁹⁸Cd

| (8+)

|-id=Cadmium-98m2

| style="text-indent:1em" | ^98m2Cd

| colspan="3" style="text-indent:2em" | 6635(2) keV

| 224(5) ns

| IT

| ⁹⁸Cd

| (12+)

|-id=Cadmium-99

| rowspan=3|⁹⁹Cd

| rowspan=3 style="text-align:right" | 48

| rowspan=3 style="text-align:right" | 51

| rowspan=3|98.9249258(17)

| rowspan=3|17(1) s

| β⁺ (99.79%)

| ⁹⁹Ag

| rowspan=3|5/2+#

| rowspan=3|

| β⁺, p (0.21%)

| ⁹⁸Pd

| β⁺, α (<10⁻⁴%)

| ⁹⁵Rh

|-id=Cadmium-100

| ¹⁰⁰Cd

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

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

| 99.9203488(18)

| 49.1(5) s

| β⁺

| ¹⁰⁰Ag

| 0+

|-id=Cadmium-101

| ¹⁰¹Cd

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

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

| 100.9185862(16)

| 1.36(5) min

| β⁺

| ¹⁰¹Ag

| 5/2+

|-id=Cadmium-102

| ¹⁰²Cd

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

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

| 101.9144818(18)

| 5.5(5) min

| β⁺

| ¹⁰²Ag

| 0+

|-id=Cadmium-103

| ¹⁰³Cd

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

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

| 102.9134169(19)

| 7.3(1) min

| β⁺

| ¹⁰³Ag

| 5/2+

|-id=Cadmium-104

| ¹⁰⁴Cd

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

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

| 103.9098562(18)

| 57.7(10) min

| β⁺

| ¹⁰⁴Ag

| 0+

|-id=Cadmium-105

| ¹⁰⁵Cd

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

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

| 104.9094639(15)

| 55.5(4) min

| β⁺

| ¹⁰⁵Ag

| 5/2+

|-id=Cadmium-105m

| style="text-indent:1em" | ^105mCd

| colspan="3" style="text-indent:2em" | 2517.6(5) keV

| 4.5(5) μs

| IT

| ¹⁰⁵Cd

| (21/2+)

|-id=Cadmium-106

| ¹⁰⁶Cd

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

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

| 105.9064598(12)

| colspan=3 align=center|Observationally StableBelieved to decay by β⁺β⁺ to ¹⁰⁶Pd with a half-life over 1.1×10²¹ years

| 0+

| 0.01245(22)

|-id=Cadmium-107

| ¹⁰⁷Cd

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

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

| 106.9066120(18)

| 6.50(2) h

| β⁺

| ¹⁰⁷Ag

| 5/2+

|-id=Cadmium-108

| ¹⁰⁸Cd

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

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

| 107.9041836(12)

| colspan=3 align=center|Observationally StableBelieved to decay by β⁺β⁺ to ¹⁰⁸Pd with a half-life over 4.1×10¹⁷ years

| 0+

| 0.00888(11)

|-id=Cadmium-109

| ¹⁰⁹Cd

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

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

| 108.9049867(16)

| 461.3(5) d

| EC

| ¹⁰⁹Ag

| 5/2+

|-id=Cadmium-109m1

| style="text-indent:1em" | ^109m1Cd

| colspan="3" style="text-indent:2em" | 59.60(7) keV

| 11.8(16) μs

| IT

| ¹⁰⁹Cd

| 1/2+

|-id=Cadmium-109m2

| style="text-indent:1em" | ^109m2Cd

| colspan="3" style="text-indent:2em" | 463.10(11) keV

| 10.6(4) μs

| IT

| ¹⁰⁹Cd

| 11/2−

|-id=Cadmium-110

| ¹¹⁰Cd

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

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

| 109.90300747(41)

| colspan=3 align=center|Stable

| 0+

| 0.12470(61)

|-id=Cadmium-111

| ¹¹¹CdFission product

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

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

| 110.90418378(38)

| colspan=3 align=center|Stable

| 1/2+

| 0.12795(12)

|-id=Cadmium-111m

| style="text-indent:1em" | ^111mCd

| colspan="3" style="text-indent:2em" | 396.214(21) keV

| 48.50(9) min

| IT

| ¹¹¹Cd

| 11/2−

|-id=Cadmium-112

| ¹¹²Cd

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

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

| 111.90276390(27)

| colspan=3 align=center|Stable

| 0+

| 0.24109(7)

|-id=Cadmium-113

| ¹¹³CdPrimordial radionuclide

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

| style="text-align:right" | 65

| 112.90440811(26)

| 8.04(5)×10¹⁵ y

| β⁻

| ¹¹³In

| 1/2+

| 0.12227(7)

| rowspan=2 style="text-indent:1em" | ^113mCd

| rowspan=2 colspan="3" style="text-indent:2em" | 263.54(3) keV

| rowspan=2|13.89(11) y

| β⁻ (99.90%)

| ¹¹³In

| rowspan=2|11/2−

| rowspan=2|

| IT (0.0964%)

| ¹¹³Cd

|-id=Cadmium-114

| ¹¹⁴Cd

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

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

| 113.90336500(30)

| colspan=3 align=center|Observationally StableBelieved to undergo β⁻β⁻ decay to ¹¹⁴Sn with a half-life over 9.2×10¹⁶ years

| 0+

| 0.28754(81)

|-id=Cadmium-115

| ¹¹⁵Cd

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

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

| 114.90543743(70)

| 53.46(5) h

| β⁻

| ^115mIn

| 1/2+

|-id=Cadmium-115m

| style="text-indent:1em" | ^115mCd

| colspan="3" style="text-indent:2em" | 181.0(5) keV

| 44.56(24) d

| β⁻

| ^115mIn

| 11/2−

|-id=Cadmium-116

| ¹¹⁶Cd

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

| style="text-align:right" | 68

| 115.90476323(17)

| 2.69(9)×10¹⁹ y

| β⁻β⁻

| ¹¹⁶Sn

| 0+

| 0.07512(54)

|-id=Cadmium-117

| ¹¹⁷Cd

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

| style="text-align:right" | 69

| 116.9072260(11)

| 2.503(5) h

| β⁻

| ¹¹⁷In

| 1/2+

|-id=Cadmium-117m

| style="text-indent:1em" | ^117mCd

| colspan="3" style="text-indent:2em" | 136.4(2) keV

| 3.441(9) h

| β⁻

| ¹¹⁷In

| 11/2−

|-id=Cadmium-118

| ¹¹⁸Cd

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

| style="text-align:right" | 70

| 117.906922(21)

| 50.3(2) min

| β⁻

| ¹¹⁸In

| 0+

|-id=Cadmium-119

| ¹¹⁹Cd

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

| style="text-align:right" | 71

| 118.909847(40)

| 2.69(2) min

| β⁻

| ¹¹⁹In

| 1/2+

|-id=Cadmium-119m

| style="text-indent:1em" | ^119mCd

| colspan="3" style="text-indent:2em" | 146.54(11) keV

| 2.20(2) min

| β⁻

| ¹¹⁹In

| 11/2−

|-id=Cadmium-120

| ¹²⁰Cd

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

| style="text-align:right" | 72

| 119.9098681(40)

| 50.80(21) s

| β⁻

| ¹²⁰In

| 0+

|-id=Cadmium-121

| ¹²¹Cd

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

| style="text-align:right" | 73

| 120.9129637(21)

| 13.5(3) s

| β⁻

| ¹²¹In

| 3/2+

|-id=Cadmium-121m

| style="text-indent:1em" | ^121mCd

| colspan="3" style="text-indent:2em" | 214.86(15) keV

| 8.3(8) s

| β⁻

| ¹²¹In

| 11/2−

|-id=Cadmium-122

| ¹²²Cd

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

| style="text-align:right" | 74

| 121.9134591(25)

| 5.98(10) s{{cite journal |last1=Nesterenko |first1=D. A. |last2=Ruotsalainen |first2=J. |last3=Stryjczyk |first3=M. |last4=Kankainen |first4=A. |last5=Al Ayoubi |first5=L. |last6=Beliuskina |first6=O. |last7=Delahaye |first7=P. |last8=Eronen |first8=T. |last9=Flayol |first9=M. |last10=Ge |first10=Z. |last11=Gins |first11=W. |last12=Hukkanen |first12=M. |last13=Jaries |first13=A. |last14=Kahl |first14=D. |last15=Kumar |first15=D. |last16=Nikas |first16=S. |last17=Ortiz-Cortes |first17=A. |last18=Penttilä |first18=H. |last19=Pitman-Weymouth |first19=D. |last20=Raggio |first20=A. |last21=Ramalho |first21=M. |last22=Reponen |first22=M. |last23=Rinta-Antila |first23=S. |last24=Romero |first24=J. |last25=de Roubin |first25=A. |last26=Srivastava |first26=P. C. |last27=Suhonen |first27=J. |last28=Virtanen |first28=V. |last29=Zadvornaya |first29=A. |title=High-precision measurements of low-lying isomeric states in In 120 – 124 with the JYFLTRAP double Penning trap |journal=Physical Review C |date=1 November 2023 |volume=108 |issue=5 |doi=10.1103/PhysRevC.108.054301 |arxiv=2306.11505}}

| β⁻

| ¹²²In

| 0+

|-id=Cadmium-123

| ¹²³Cd

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

| style="text-align:right" | 75

| 122.9168925(29)

| 2.10(2) s

| β⁻

| ¹²³In

| 3/2+

|-id=Cadmium-123m

| rowspan=2 style="text-indent:1em" | ^123mCd

| rowspan=2 colspan="3" style="text-indent:2em" | 143(4) keV

| rowspan=2|1.82(3) s

| β⁻ (?%)

| ¹²³In

| rowspan=2|11/2−

| rowspan=2|

| IT (?%)

| ¹²³Cd

|-id=Cadmium-124

| ¹²⁴Cd

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

| style="text-align:right" | 76

| 123.9176598(28)

| 1.25(2) s

| β⁻

| ¹²⁴In

| 0+

|-id=Cadmium-125

| ¹²⁵Cd

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

| style="text-align:right" | 77

| 124.9212576(31)

| 680(40) ms

| β⁻

| ¹²⁵In

| 3/2+

|-id=Cadmium-125m1

| style="text-indent:1em" | ^125m1Cd

| colspan="3" style="text-indent:2em" | 186(4) keV

| 480(30) ms

| β⁻

| ¹²⁵In

| 11/2−

|-id=Cadmium-125m2

| style="text-indent:1em" | ^125m2Cd

| colspan="3" style="text-indent:2em" | 1648(4) keV

| 19(3) μs

| IT

| ¹²⁵Cd

| (19/2+)

|-id=Cadmium-126

| ¹²⁶Cd

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

| style="text-align:right" | 78

| 125.9224303(25)

| 512(5) ms

| β⁻

| ¹²⁶In

| 0+

|-id=Cadmium-127

| ¹²⁷Cd

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

| style="text-align:right" | 79

| 126.9262033(67)

| 480(100) ms

| β⁻

| ¹²⁷In

| 3/2+

|-id=Cadmium-127m1

| style="text-indent:1em" | ^127m1Cd

| colspan="3" style="text-indent:2em" | 285(8) keV

| 360(40) ms

| β⁻

| ¹²⁷In

| 11/2−

|-id=Cadmium-127m2

| style="text-indent:1em" | ^127m2Cd

| colspan="3" style="text-indent:2em" | 1845(8) keV

| 17.5(3) μs

| IT

| ¹²⁷Cd

| (19/2+)

|-id=Cadmium-128

| ¹²⁸Cd

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

| style="text-align:right" | 80

| 127.9278168(69)

| 246(2) ms

| β⁻

| ¹²⁸In

| 0+

|-id=Cadmium-128m1

| style="text-indent:1em" | ^128m1Cd

| colspan="3" style="text-indent:2em" | 1870.5(3) keV

| 270(7) ns

| IT

| ¹²⁸Cd

| (5−)

|-id=Cadmium-128m2

| style="text-indent:1em" | ^128m2Cd

| colspan="3" style="text-indent:2em" | 2714.6(4) keV

| 3.56(6) μs

| IT

| ¹²⁸Cd

| (10+)

|-id=Cadmium-128m2

| style="text-indent:1em" | ^128m2Cd

| colspan="3" style="text-indent:2em" | 4286.6(15) keV

| 6.3(8) ms

| IT

| ¹²⁸Cd

| (15−)

|-id=Cadmium-129

| rowspan=2|¹²⁹Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 81

| rowspan=2|128.9322356(57)

| rowspan=2|147(3) ms

| β⁻ (?%)

| ¹²⁹In

| rowspan=2|11/2−

| rowspan=2|

| β⁻, n (?%)

| ¹²⁸In

|-id=Cadmium-129m1

| rowspan=2 style="text-indent:1em" | ^129m1Cd

| rowspan=2 colspan="3" style="text-indent:2em" | 343(8) keV

| rowspan=2|157(8) ms

| β⁻ (?%)

| ¹²⁹In

| rowspan=2|3/2+

| rowspan=2|

| β⁻, n (?%)

| ¹²⁸In

|-id=Cadmium-129m2

| style="text-indent:1em" | ^129m2Cd

| colspan="3" style="text-indent:2em" | 2283(8) keV

| 3.6(2) ms

| IT

| ¹²⁹Cd

| (21/2+)

|-id=Cadmium-130

| rowspan=2|¹³⁰Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 82

| rowspan=2|129.934388(24)

| rowspan=2|126.8(18) ms

| β⁻ (96.5%)

| ¹³⁰In

| rowspan=2|0+

| rowspan=2|

| β⁻, n (3.5%)

| ¹²⁹In

|-id=Cadmium-130m

| style="text-indent:1em" | ^130mCd

| colspan="3" style="text-indent:2em" | 2129.6(10) keV

| 240(16) ns

| IT

| ¹³⁰Cd

| (8+)

|-id=Cadmium-131

| rowspan=2|¹³¹Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 83

| rowspan=2|130.940728(21)

| rowspan=2|98(2) ms

| β⁻ (96.5%)

| ¹³¹In

| rowspan=2|7/2−#

| rowspan=2|

| β⁻, n (3.5%)

| ¹³⁰In

|-id=Cadmium-132

| rowspan=2|¹³²Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 84

| rowspan=2|131.945823(64)

| rowspan=2|84(5) ms

| β⁻, n (60%)

| ¹³¹In

| rowspan=2|0+

| rowspan=2|

| β⁻ (40%)

| ¹³²In

|-id=Cadmium-133

| rowspan=2|¹³³Cd

| rowspan=2 style="text-align:right" | 48

| rowspan=2 style="text-align:right" | 85

| rowspan=2|132.95261(22)#

| rowspan=2|61(6) ms

| β⁻ (?%)

| ¹³³In

| rowspan=2|7/2−#

| rowspan=2|

| β⁻, n (?%)

| ¹³²In

|-id=Cadmium-134

| ¹³⁴Cd

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

| style="text-align:right" | 86

| 133.95764(32)#

| 65(15) ms

| β⁻

| ¹³⁴In

| 0+

Hyperdeformation is predicted to be found in ¹⁰⁷Cd.

Cadmium-113m

Cadmium-113m is a cadmium radioisotope and nuclear isomer with a half-life of 14.1 years. In a normal thermal reactor, it has a very low fission product yield, plus its large neutron capture cross section means that most of even the small amount produced is destroyed in the course of the nuclear fuel's burnup; thus, this isotope is not a significant contributor to nuclear waste.

Fast fission or fission of some heavier actinides{{which|date=May 2018}} will produce ^113mCd at higher yields.

References

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}}

Category:Cadmium

Cadmium