# Isotopen van lanthaan

Het chemisch element lanthaan (La), met een atoommassa van 138,90547(7) u, bezit 1 stabiele isotoop: $^{139}$La, met een abundant van 99,9%. Het overige in de natuur voorkomende isotoop is de radio-isotoop $^{138}$La. De 38 radio-isotopen zijn onstabiel en hebben een relatief korte halveringstijd (de meeste minder dan een seconde).
De kortstlevende isotoop van lanthaan is $^{117}$La, met een halfwaardetijd van ongeveer 23,5 milliseconden. De langstlevende is $^{138}$La, met een halfwaardetijd van 102 miljard jaar. Deze isotoop is een radioactief primordiaal nuclide dat in kleine hoeveelheden op Aarde voorkomt (0,09%). Het vervalt voor 66,4% door β$^+$-verval tot de stabiele isotoop barium-138 en voor 33,6% door β$^−$-verval tot de stabiele isotoop cerium-138:
    ${\ce {{^{138}_{57}La}->{^{138}_{56}Ba}+{e^{+}}+{\nu }_{e}}}$
    ${\ce {{^{138}_{57}La}->{^{138}_{58}Ce}+{e^{-}}+{\bar {\nu }}_{e}}}$

## Overzicht

| Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | VP | Kernspin | Isotopische verhouding (molfractie) |
| Natuurlijk voorkomen (molfractie) |||
| $^{117}$La | 57 | 60 | 116,95007(43) | 23,5(26) ms | β$^+$ | $^{117}$Ba | (3/2$^+$, 3/2$^−$) | |
| $^{117}$La | 57 | 60 | 116,95007(43) | 23,5(26) ms | p | $^{116}$Ba | (3/2$^+$, 3/2$^−$) | |
| $^{117m}$La | 151(12) keV | 151(12) keV | 151(12) keV | 10(5) ms | | | (9/2$^+$) | |
| $^{118}$La | 57 | 61 | 117,94673(32) | 200 ms | β$^+$ | $^{118}$Ba | | |
| $^{119}$La | 57 | 62 | 118,94099(43) | 1 s | β$^+$ | $^{119}$Ba | 11/2$^−$ | |
| $^{120}$La | 57 | 63 | 119,93807(54) | 2,8(2) s | β$^+$ | $^{120}$Ba | | |
| $^{120}$La | 57 | 63 | 119,93807(54) | 2,8(2) s | β$^+$, p | $^{119}$Cs | | |
| $^{121}$La | 57 | 64 | 120,93301(54) | 5,3(2) s | β$^+$ | $^{121}$Ba | 11/2$^−$ | |
| $^{121}$La | 57 | 64 | 120,93301(54) | 5,3(2) s | β$^+$, p | $^{120}$Cs | 11/2$^−$ | |
| $^{122}$La | 57 | 65 | 121,93071(32) | 8,6(5) s | β$^+$ | $^{122}$Ba | | |
| $^{122}$La | 57 | 65 | 121,93071(32) | 8,6(5) s | β$^+$, p | $^{121}$Cs | | |
| $^{123}$La | 57 | 66 | 122,92624(21) | 17(3) s | β$^+$ | $^{123}$Ba | 11/2$^−$ | |
| $^{124}$La | 57 | 67 | 123,92457(6) | 29,21(17) s | β$^+$ | $^{124}$Ba | (7$^−$, 8$^−$) | |
| $^{124m}$La | 100(100) keV | 100(100) keV | 100(100) keV | 21(4) s | | | | |
| $^{125}$La | 57 | 68 | 124,920816(28) | 64,8(12) s | β$^+$ | $^{125}$Ba | (11/2$^−$) | |
| $^{125m}$La | 107,0(10) keV | 107,0(10) keV | 107,0(10) keV | 390(40) ms | | | (3/2$^+$) | |
| $^{126}$La | 57 | 69 | 125,91951(10) | 54(2) s | β$^+$ | $^{126}$Ba | (5$^+$) | |
| $^{126m}$La | 210(410) keV | 210(410) keV | 210(410) keV | 20(20) s | | | (0$^−$, 1$^−$, 2$^−$) | |
| $^{127}$La | 57 | 70 | 126,916375(28) | 5,1(1) min | β$^+$ | $^{127}$Ba | (11/2$^−$) | |
| $^{127m}$La | 14,8(12) keV | 14,8(12) keV | 14,8(12) keV | 3,7(4) min | β$^+$ | $^{127}$Ba | (3/2$^+$) | |
| $^{127m}$La | 14,8(12) keV | 14,8(12) keV | 14,8(12) keV | 3,7(4) min | IT | $^{127}$La | (3/2$^+$) | |
| $^{128}$La | 57 | 71 | 127,91559(6) | 5,18(14) min | β$^+$ | $^{128}$Ba | (5$^+$) | |
| $^{128m}$La | 100(100) keV | 100(100) keV | 100(100) keV | < 1,4 min | IT | $^{128}$La | (1$^+$, 2$^−$) | |
| $^{129}$La | 57 | 72 | 128,912693(22) | 11,6(2) min | β$^+$ | $^{129}$Ba | 3/2$^+$ | |
| $^{129m}$La | 172,1(4) keV | 172,1(4) keV | 172,1(4) keV | 560(50) ms | IT | $^{129}$La | 11/2$^−$ | |
| $^{130}$La | 57 | 73 | 129,912369(28) | 8,7(1) min | β$^+$ | $^{130}$Ba | 3$^+$ | |
| $^{131}$La | 57 | 74 | 130,91007(3) | 59(2) min | β$^+$ | $^{131}$Ba | 3/2$^+$ | |
| $^{131m}$La | 304,52(24) keV | 304,52(24) keV | 304,52(24) keV | 170(10) µs | | | 11/2$^−$ | |
| $^{132}$La | 57 | 75 | 131,91010(4) | 4,8(2) uur | β$^+$ | $^{132}$Ba | 2$^−$ | |
| $^{132m}$La | 188,18(11) keV | 188,18(11) keV | 188,18(11) keV | 24,3(5) min | IT (76%) | $^{132}$La | 6$^−$ | |
| $^{132m}$La | 188,18(11) keV | 188,18(11) keV | 188,18(11) keV | 24,3(5) min | β$^+$ (24%) | $^{132}$Ba | 6$^−$ | |
| $^{133}$La | 57 | 76 | 132,90822(3) | 3,912(8) uur | β$^+$ | $^{133}$Ba | 5/2$^+$ | |
| $^{134}$La | 57 | 77 | 133,908514(21) | 6,45(16) min | β$^+$ | $^{134}$Ba | 1$^+$ | |
| $^{135}$La | 57 | 78 | 134,906977(11) | 19,5(2) uur | β$^+$ | $^{135}$Ba | 5/2$^+$ | |
| $^{136}$La | 57 | 79 | 135,90764(6) | 9,87(3) min | β$^+$ | $^{136}$Ba | 1$^+$ | |
| $^{136m}$La | 255(9) keV | 255(9) keV | 255(9) keV | 114(3) ms | IT | $^{136}$La | (8$^−$) | |
| $^{137}$La | 57 | 80 | 136,906494(14) | 6(2)E × 10$^4$ jaar | EV | $^{137}$Ba | 7/2$^+$ | |
| $^{138}$La | 57 | 81 | 137,907112(4) | 1,02(1) × 10$^{11}$ jaar | β$^+$ (66,4%) | $^{138}$Ba | 5$^+$ | 9,0(1) × 10$^{−4}$ |
| $^{138}$La | 57 | 81 | 137,907112(4) | 1,02(1) × 10$^{11}$ jaar | β$^−$ (33,6%) | $^{138}$Ce | 5$^+$ | 9,0(1) × 10$^{−4}$ |
| $^{138m}$La | 72,57(3) keV | 72,57(3) keV | 72,57(3) keV | 116(5) ns | | | 3$^+$ | |
| $^{139}$La | 57 | 82 | 138,9063533(26) | stabiel | stabiel | stabiel | 7/2$^+$ | 0,99910(1) |
| $^{140}$La | 57 | 83 | 139,9094776(26) | 1,6781(3) dagen | β$^−$ | $^{140}$Ce | 3$^−$ | |
| $^{141}$La | 57 | 84 | 140,910962(5) | 3,92(3) uur | β$^−$ | $^{141}$Ce | (7/2$^+$) | |
| $^{142}$La | 57 | 85 | 141,914079(6) | 91,1(5) min | β$^−$ | $^{142}$Ce | 2$^−$ | |
| $^{143}$La | 57 | 86 | 142,916063(17) | 14,2(1) min | β$^−$ | $^{143}$Ce | 7/2$^+$ | |
| $^{144}$La | 57 | 87 | 143,91960(5) | 40,8(4) s | β$^−$ | $^{144}$Ce | (3$^−$) | |
| $^{145}$La | 57 | 88 | 144,92165(10) | 24,8(20) s | β$^−$ | $^{145}$Ce | (5/2$^+$) | |
| $^{146}$La | 57 | 89 | 145,92579(8) | 6,27(10) s | β$^−$ (99,99%) | $^{146}$Ce | 2$^−$ | |
| $^{146}$La | 57 | 89 | 145,92579(8) | 6,27(10) s | β$^−$, n (0,007%) | $^{145}$Ce | 2$^−$ | |
| $^{146m}$La | 130(130) keV | 130(130) keV | 130(130) keV | 10,0(1) s | β$^−$ | $^{146}$Ce | (6$^−$) | |
| $^{147}$La | 57 | 90 | 146,92824(5) | 4,015(8) s | β$^−$ (99,96%) | $^{147}$Ce | (5/2$^+$) | |
| $^{147}$La | 57 | 90 | 146,92824(5) | 4,015(8) s | β$^−$, n (0,04%) | $^{146}$Ce | (5/2$^+$) | |
| $^{148}$La | 57 | 91 | 147,93223(6) | 1,26(8) s | β$^−$ (99,85%) | $^{148}$Ce | (2$^−$) | |
| $^{148}$La | 57 | 91 | 147,93223(6) | 1,26(8) s | β$^−$, n (0,15%) | $^{147}$Ce | (2$^−$) | |
| $^{149}$La | 57 | 92 | 148,93473(34) | 1,05(3) s | β$^−$ (98,6%) | $^{149}$Ce | 5/2$^+$ | |
| $^{149}$La | 57 | 92 | 148,93473(34) | 1,05(3) s | β$^−$, n (1,4%) | $^{148}$Ce | 5/2$^+$ | |
| $^{150}$La | 57 | 93 | 149,93877(43) | 510(30) ms | β$^−$ (97,3%) | $^{150}$Ce | (3$^+$) | |
| $^{150}$La | 57 | 93 | 149,93877(43) | 510(30) ms | β$^−$, n (2,7%) | $^{149}$Ce | (3$^+$) | |
| $^{151}$La | 57 | 94 | 150,94172(43) | 300 ms | β$^−$ | $^{151}$Ce | 5/2$^+$ | |
| $^{152}$La | 57 | 95 | 151,94625(43) | 200 ms | β$^−$ | $^{152}$Ce | | |
| $^{153}$La | 57 | 96 | 152,94962(64) | 150 ms | β$^−$ | $^{153}$Ce | 5/2$^+$ | |
| $^{154}$La | 57 | 97 | 153,95450(64) | 100 ms | β$^−$ | $^{154}$Ce | | |
| $^{155}$La | 57 | 98 | 154,95835(86) | 60 ms | β$^−$ | $^{155}$Ce | 5/2$^+$ | |

## Overzicht van isotopen per element

* (en) R.B. Firestone, S.Y. Frank Chu & C.M. Baglin (1999) - Table of Isotopes (online versie van de cd-rom)
* (en) G. Audi, A.H. Wapstra, C. Thibault, J. Blachot & O. Bersillon (2003) - The NUBASE evaluation of nuclear and decay properties, Nuclear Physics A, 729, pp. 3-128
* (en) J.R. de Laeter, J.K. Böhlke, P. De Bièvre, H. Hidaka, H.S. Peiser, K.J.R. Rosman & P.D.P. Taylor (2003) - Atomic weights of the elements. Review 2000 (IUPAC Technical Report), Pure and Applied Chemistry, 75 (6), pp. 683–800
* (en) M.E. Wieser (2006) - Atomic weights of the elements 2005 (IUPAC Technical Report), Pure and Applied Chemistry, 78 (11), pp. 2051–2066
* (en) David R. Lide (2004) - CRC Handbook of Chemistry and Physics (85th ed.), hoofdstuk 11, CRC Press - ISBN 978-0849304859
* ↑ (en) WolframAlpha
$^{116}$La · $^{117}$La · $^{117m}$La · $^{118}$La · $^{119}$La · $^{120}$La · $^{121}$La · $^{122}$La · $^{123}$La · $^{124}$La · $^{124m}$La · $^{125}$La · $^{125m}$La · $^{126}$La · $^{126m}$La · $^{127}$La · $^{127m}$La · $^{128}$La · $^{128m}$La · $^{129}$La · $^{129m}$La · $^{130}$La · $^{131}$La · $^{131m}$La · $^{132}$La · $^{132m}$La · $^{133}$La · $^{134}$La · $^{135}$La · $^{136}$La · $^{136m}$La · $^{137}$La · $^{138}$La · $^{138m}$La · $^{139}$La · $^{140}$La · $^{141}$La · $^{142}$La · $^{143}$La · $^{144}$La · $^{145}$La · $^{146}$La · $^{146m}$La · $^{147}$La · $^{148}$La · $^{149}$La · $^{150}$La · $^{151}$La · $^{152}$La · $^{153}$La · $^{154}$La · $^{155}$La · $^{156}$La