Login
Login

Isotopes of lanthanum

{{Short description|Isotopes}}

{{Infobox lanthanum isotopes}}

File:Lanthanum stable nucleus.png

Naturally occurring lanthanum (57La) is composed of one stable (139La) and one radioactive (138La) isotope, with the stable isotope, 139La, being the most abundant (99.91% natural abundance). There are 39 radioisotopes that have been characterized, with the most stable being 138La, with a half-life of 1.03×1011 years; 137La, with a half-life of 60,000 years and 140La, with a half-life of 1.6781 days. The remaining radioactive isotopes have half-lives that are less than a day and the majority of these have half-lives that are less than 1 minute. This element also has 12 nuclear isomers, the longest-lived of which is 132mLa, with a half-life of 24.3 minutes. Lighter isotopes mostly decay to isotopes of barium and heavy ones mostly decay to isotopes of cerium. 138La can decay to both.

The isotopes of lanthanum range in atomic weight from 115.96 u (116La) to 154.96 u (155La).

List of isotopes

{{Anchor}}

{{Isotopes table

|symbol=La

|refs=NUBASE2020, AME2020 II

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

}}

|-id=Lanthanum-116

| rowspan=2|116La{{cite journal |last1=Zhang |first1=Wei |last2=Cederwall |first2=Bo |last3=Aktas |first3=Özge |last4=Liu |first4=Xiaoyu |last5=Ertoprak |first5=Aysegül |last6=Nyberg |first6=Ayse |last7=Auranen |first7=Kalle |last8=Alayed |first8=Betool |last9=Badran |first9=Hussam |last10=Boston |first10=Helen |last11=Doncel |first11=Maria |last12=Forsberg |first12=Ulrika |last13=Grahn |first13=Tuomas |last14=Greenlees |first14=Paul T. |last15=Guo |first15=Song |last16=Heery |first16=Jacob |last17=Hilton |first17=Joshua |last18=Jenkins |first18=David |last19=Julin |first19=Rauno |last20=Juutinen |first20=Sakari |last21=Luoma |first21=Minna |last22=Neuvonen |first22=Olavi |last23=Ojala |first23=Joonas |last24=Page |first24=Robert D. |last25=Pakarinen |first25=Janne |last26=Partanen |first26=Jari |last27=Paul |first27=Edward S. |last28=Petrache |first28=Costel |last29=Rahkila |first29=Panu |last30=Ruotsalainen |first30=Panu |last31=Sandzelius |first31=Mikael |last32=Sarén |first32=Jan |last33=Szwec |first33=Stuart |last34=Tann |first34=Holly |last35=Uusitalo |first35=Juha |last36=Wadsworth |first36=Robert |title=Observation of the proton emitter {{ComplexNuclide|La|116|q=59}} |journal=Communications Physics |date=14 November 2022 |volume=5 |issue=1 |pages=1–8 |doi=10.1038/s42005-022-01069-w |s2cid=253512231 |issn=2399-3650|doi-access=free |url=https://jyx.jyu.fi/bitstream/123456789/84039/1/s42005-022-01069-w.pdf }}

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

| rowspan=2 style="text-align:right" | 59

| rowspan=2|115.95701(35)#

| rowspan=2|50(22) ms

| p (~60%)

| 115Ba

| rowspan=2|

| rowspan=2|

| rowspan=2|

|-

| β+ (~40%)

| 116Ba

|-id=Lanthanum-116m

| style="text-indent:1em" | 116mLa

| colspan="3" style="text-indent:2em" | 182 keV

| {{val|2.0|2.8|0.8|u=μs}}

| IT

| 116La

|

|

|

|-id=Lanthanum-117

| rowspan=2|117La

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

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

| rowspan=2|116.95033(22)#

| rowspan=2|21.6(31) ms

| p (94%)

| 116Ba

| rowspan=2|(3/2+)

| rowspan=2|

| rowspan=2|

|-

| β+ (6%)

| 117Ba

|-id=Lanthanum-117m

| style="text-indent:1em" | 117mLa

| colspan="3" style="text-indent:2em" | 192 keV

| {{val|3.9|1.9|0.9|u=μs}}

| IT

| 117La

| (7/2−)

|

|

|-id=Lanthanum-120

| rowspan=2|120La

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

| rowspan=2 style="text-align:right" | 63

| rowspan=2|119.93820(32)#

| rowspan=2|2.8(2) s

| β+

| 120Ba

| rowspan=2|4+{{cite journal |last1=Jodidar |first1=P.M. |last2=Petrache |first2=C.M. |last3=Lv |first3=B.F. |last4=Lawrie |first4=E.A. |last5=Astier |first5=A. |last6=Guo |first6=S. |last7=Zheng |first7=K.K. |last8=Auranen |first8=K. |last9=Briscoe |first9=A.D. |last10=Grahn |first10=T. |last11=Greenlees |first11=P.T. |last12=Illana |first12=A. |last13=Joukainen |first13=H. |last14=Julin |first14=R. |last15=Louko |first15=J. |last16=Luoma |first16=M. |last17=Jutila |first17=H. |last18=Ojala |first18=J. |last19=Pakarinen |first19=J. |last20=Plaza |first20=A.M. |last21=Rahkila |first21=P. |last22=Ruotsalainen |first22=P. |last23=Sarén |first23=J. |last24=Tolosa-Delgado |first24=A. |last25=Uusitalo |first25=J. |last26=Zimba |first26=G. |last27=Kuti |first27=I. |last28=Krakó |first28=A. |last29=Andreoiu |first29=C. |last30=Joss |first30=D.T. |last31=Page |first31=R.D. |last32=Cederlöf |first32=E.A. |last33=Ertoprak |first33=A. |title=First observation of excited states in 120La and its impact on the shape evolution in the A ≈ 120 mass region |journal=Physics Letters B |date=August 2024 |volume=855 |pages=138806 |doi=10.1016/j.physletb.2024.138806|url=https://jyx.jyu.fi/bitstream/123456789/96806/1/1-s2.0-S0370269324003642-main.pdf }}

| rowspan=2|

| rowspan=2|

|-

| β+, p (?%)

| 119Cs

|-id=Lanthanum-121

| 121La

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

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

| 120.93324(32)#

| 5.3(2) s

| β+

| 121Ba

| 11/2−#

|

|

|-id=Lanthanum-122

| rowspan=2|122La

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

| rowspan=2 style="text-align:right" | 65

| rowspan=2|121.93071(32)#

| rowspan=2|8.6(5) s

| β+

| 122Ba

| rowspan=2|2+

| rowspan=2|

| rowspan=2|

|-

| β+, p (?%)

| 121Cs

|-id=Lanthanum-123

| 123La

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

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

| 122.92630(21)#

| 17(3) s

| β+

| 123Ba

| 11/2−#

|

|

|-id=Lanthanum-124

| 124La

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

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

| 123.924574(61)

| 29.21(17) s

| β+

| 124Ba

| (7−, 8−)

|

|

|-id=Lanthanum-124m

| style="text-indent:1em" | 124mLaOrder of ground state and isomer is uncertain.

| colspan="3" style="text-indent:2em" | 100(100)# keV

| 21(4) s

| β+

| 124Ba

| 2−#

|

|

|-id=Lanthanum-125

| 125La

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

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

| 124.920816(28)

| 64.8(12) s

| β+

| 125Ba

| 11/2−#

|

|

|-id=Lanthanum-125m

| style="text-indent:1em" | 125mLa

| colspan="3" style="text-indent:2em" | 107.00(10) keV

| 390(40) ms

| IT

| 125La

| (3/2+)

|

|

|-id=Lanthanum-126

| 126La

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

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

| 125.919513(97)

| 54(2) s

| β+

| 126Ba

| 5−#

|

|

|-id=Lanthanum-126m

| style="text-indent:1em" | 126mLa

| colspan="3" style="text-indent:2em" | 210(410) keV

| 20(20) s

| β+

| 126Ba

| 1−#

|

|

|-id=Lanthanum-127

| 127La

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

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

| 126.916375(28)

| 5.1(1) min

| β+

| 127Ba

| (11/2−)

|

|

|-id=Lanthanum-127m

| style="text-indent:1em" | 127mLa

| colspan="3" style="text-indent:2em" | 14.2(4) keV

| 3.7(4) min

| β+

| 127Ba

| (3/2+)

|

|

|-id=Lanthanum-128

| 128La

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

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

| 127.915592(58)

| 5.18(14) min

| β+

| 128Ba

| (5+)

|

|

|-id=Lanthanum-128m

| style="text-indent:1em" | 128mLa

| colspan="3" style="text-indent:2em" | 100(100)# keV

| <1.4 min

| β+

| 128Ba

| (1+, 2−)

|

|

|-id=Lanthanum-129

| 129La

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

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

| 128.912696(23)

| 11.6(2) min

| β+

| 129Ba

| (3/2+)

|

|

|-id=Lanthanum-129m

| style="text-indent:1em" | 129mLa

| colspan="3" style="text-indent:2em" | 172.33(20) keV

| 560(50) ms

| IT

| 129La

| (11/2−)

|

|

|-id=Lanthanum-130

| 130La

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

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

| 129.912369(28)

| 8.7(1) min

| β+

| 130Ba

| 3(+)

|

|

|-id=Lanthanum-130m

| style="text-indent:1em" | 130mLa

| colspan="3" style="text-indent:2em" | 214.0(5) keV

| 742(28) ns

| IT

| 130La

| (5+)

|

|

|-id=Lanthanum-131

| 131La

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

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

| 130.910070(30)

| 59(2) min

| β+

| 131Ba

| 3/2+

|

|

|-id=Lanthanum-131m

| style="text-indent:1em" | 131mLa

| colspan="3" style="text-indent:2em" | 304.52(24) keV

| 170(10) μs

| IT

| 131La

| 11/2−

|

|

|-id=Lanthanum-132

| 132La

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

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

| 131.910119(39)

| 4.59(4) h

| β+

| 132Ba

| 2−

|

|

|-id=Lanthanum-132m

| rowspan=2 style="text-indent:1em" | 132mLa

| rowspan=2 colspan="3" style="text-indent:2em" | 188.20(11) keV

| rowspan=2|24.3(5) min

| IT (76%)

| 132La

| rowspan=2|6−

| rowspan=2|

| rowspan=2|

|-

| β+ (24%)

| 132Ba

|-id=Lanthanum-133

| 133La

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

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

| 132.908218(30)

| 3.912(8) h

| β+

| 133Ba

| 5/2+

|

|

|-id=Lanthanum-134

| 134La

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

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

| 133.908514(21)

| 6.45(16) min

| β+

| 134Ba

| 1+

|

|

|-id=Lanthanum-134m

| style="text-indent:1em" | 134mLa

| colspan="3" style="text-indent:2em" | 440(100)# keV

| 29(4) μs

| IT

| 134La

| (6−)

|

|

|-id=Lanthanum-135

| 135La

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

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

| 134.906984(10)

| 18.91(2) h

| β+

| 135Ba

| 5/2+

|

|

|-id=Lanthanum-136

| 136La

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

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

| 135.907635(57)

| 9.87(3) min

| β+

| 136Ba

| 1+

|

|

|-id=Lanthanum-136m1

| style="text-indent:1em" | 136m1La

| colspan="3" style="text-indent:2em" | 259.5(3) keV

| 114(5) ms

| IT

| 136La

| (7−)

|

|

|-id=Lanthanum-136m2

| style="text-indent:1em" | 136m2La

| colspan="3" style="text-indent:2em" | 2520.6(4) keV

| 187(27) ns

| IT

| 136La

| (14+)

|

|

|-id=Lanthanum-137

| 137La

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

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

| 136.9064504(18)

| 6(2)×104 y

| EC

| 137Ba

| 7/2+

|

|

|-id=Lanthanum-137m

| style="text-indent:1em" | 137mLa

| colspan="3" style="text-indent:2em" | 1869.50(21) keV

| 342(25) ns

| IT

| 137La

| 19/2−

|

|

|-id=Lanthanum-138

| rowspan=2|138LaPrimordial radionuclide

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

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

| rowspan=2|137.90712404(45)

| rowspan=2|1.03(1)×1011 y

| β+ (65.5%)

| 138Ba

| rowspan=2|5+

| rowspan=2|8.881(71)×10−4

| rowspan=2|

|-

| β− (34.5%)

| 138Ce

|-id=Lanthanum-138m1

| style="text-indent:1em" | 138m1La

| colspan="3" style="text-indent:2em" | 72.57(3) keV

| 116(5) ns

| IT

| 138La

| (3)+

|

|

|-id=Lanthanum-138m2

| style="text-indent:1em" | 138m2La

| colspan="3" style="text-indent:2em" | 738.80(20) keV

| 2.0(3) μs

| IT

| 138La

| 7−

|

|

|-id=Lanthanum-139

| 139LaFission product

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

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

| 138.90636293(65)

| colspan=3 align=center|Stable

| 7/2+

| 0.9991119(71)

|

|-id=Lanthanum-139m

| style="text-indent:1em" | 139mLa

| colspan="3" style="text-indent:2em" | 1800.4(4) keV

| 315(35) ns

| IT

| 139La

| (17/2+)

|

|

|-id=Lanthanum-140

| 140La

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

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

| 139.90948729(65)

| 40.289(4) h

| β−

| 140Ce

| 3−

|

|

|-id=Lanthanum-141

| 141La

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

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

| 140.9109712(44)

| 3.92(3) h

| β−

| 141Ce

| (7/2+)

|

|

|-id=Lanthanum-142

| 142La

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

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

| 141.9140908(67)

| 91.1(5) min

| β−

| 142Ce

| 2−

|

|

|-id=Lanthanum-142m

| style="text-indent:1em" | 142mLa

| colspan="3" style="text-indent:2em" | 145.82(8) keV

| 0.87(17) μs

| IT

| 142La

| (4)−

|

|

|-id=Lanthanum-143

| 143La

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

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

| 142.9160795(79)

| 14.2(1) min

| β−

| 143Ce

| (7/2)+

|

|

|-id=Lanthanum-144

| 144La

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

| style="text-align:right" | 87

| 143.919646(14)

| 44.0(7) s

| β−

| 144Ce

| (3−)

|

|

|-id=Lanthanum-145

| 145La

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

| style="text-align:right" | 88

| 144.921808(13)

| 24.8(20) s

| β−

| 145Ce

| (5/2+)

|

|

|-id=Lanthanum-146

| 146La

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

| style="text-align:right" | 89

| 145.9256880(18)

| 9.9(1) s

| β−

| 146Ce

| (5−)

|

|

|-id=Lanthanum-146m

| style="text-indent:1em" | 146mLa

| colspan="3" style="text-indent:2em" | 141.5(24) keV

| 6.08(22) s

| β−

| 146Ce

| (1−, 2−)

|

|

|-id=Lanthanum-147

| rowspan=2|147La

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

| rowspan=2 style="text-align:right" | 90

| rowspan=2|146.928418(12)

| rowspan=2|4.026(20) s

| β− (99.96%)

| 147Ce

| rowspan=2|(5/2+)

| rowspan=2|

| rowspan=2|

|-

| β−, n (0.041%)

| 146Ce

|-id=Lanthanum-148

| rowspan=2|148La

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

| rowspan=2 style="text-align:right" | 91

| rowspan=2|147.932679(21)

| rowspan=2|1.414(25) s

| β− (99.82%)

| 148Ce

| rowspan=2|(2−)

| rowspan=2|

| rowspan=2|

|-

| β−, n (0.18%)

| 147Ce

|-id=Lanthanum-149

| rowspan=2|149La

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

| rowspan=2 style="text-align:right" | 92

| rowspan=2|148.93535(21)

| rowspan=2|1.071(22) s

| β− (98.57%)

| 149Ce

| rowspan=2|(3/2−)

| rowspan=2|

| rowspan=2|

|-

| β−, n (1.43%)

| 148Ce

|-id=Lanthanum-150

| rowspan=2|150La

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

| rowspan=2 style="text-align:right" | 93

| rowspan=2|149.9395475(27)

| rowspan=2|504(15) ms

| β− (97.3%)

| 150Ce

| rowspan=2|(3+)

| rowspan=2|

| rowspan=2|

|-

| β−, n (2.7%)

| 149Ce

|-id=Lanthanum-151

| 151La

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

| style="text-align:right" | 94

| 150.94277(47)

| 465(24) ms

| β−

| 151Ce

| 1/2+#

|

|

|-id=Lanthanum-152

| 152La

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

| style="text-align:right" | 95

| 151.94709(32)#

| 287(16) ms

| β−

| 152Ce

| 2−#

|

|

|-id=Lanthanum-153

| 153La

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

| style="text-align:right" | 96

| 152.95055(32)#

| 245(18) ms

| β−

| 153Ce

| 1/2+#

|

|

|-id=Lanthanum-154

| 154La

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

| style="text-align:right" | 97

| 153.95542(32)#

| 161(15) ms

| β−

| 154Ce

| 2−#

|

|

|-id=Lanthanum-155

| 155La

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

| style="text-align:right" | 98

| 154.95928(43)#

| 101(28) ms

| β−

| 155Ce

| 1/2+#

|

|

|-id=Lanthanum-156

| 156La

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

| style="text-align:right" | 99

| 155.96452(43)#

| 84(78) ms

| β−

| 156Ce

| 4+#

|

|

|-id=Lanthanum-157

| 157La

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

| style="text-align:right" | 100

| 156.96879(32)#

| 30# ms
[>550 ns]

|

|

| 1/2+#

|

|

{{Isotopes table/footer}}

References

{{Reflist}}

  • 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}}

{{Navbox element isotopes}}

Category:Lanthanum

Lanthanum