# Isotopen van tantaal

Het chemisch element tantaal (Ta), met een atoommassa van 180,94788(2) u, bezit twee stabiele isotopen: $^{180m1}$Ta en $^{181}$Ta, waarvan de laatste het meest abundant is (ongeveer 99,9%). De 29 radio-isotopen zijn onstabiel en hebben een relatief korte halfwaardetijd (de meeste minder dan een seconde).
De kortstlevende isotoop van tantaal is $^{155}$Ta, met een halfwaardetijd van ongeveer 13 microseconden. De langstlevende is $^{179}$Ta, met een halfwaardetijd van 1,82 jaar.

## Tantaal-180m1

Opmerkelijk is dat een nucleair isomeer, namelijk $^{180m1}$Ta, als stabiel wordt beschouwd, omdat deze isomeren meestal een zeer korte halfwaardetijd bezitten. Het is tevens het enige in de natuur voorkomende nucleair isomeer, met een abundantie van ongeveer 0,012%. Van tantaal-180m1, met een halfwaardetijd van 20 biljard jaar, wordt vermoed dat het via enkele radioactieve vervalroutes overgaat in andere isotopen:
* Via isomerische transitie naar de radio-isotoop tantaal-180
* Via β$^−$-verval naar de stabiele isotoop wolfraam-180
* Via elektronenvangst naar de stabiele isotoop hafnium-180
Toch is geen enkel van bovenstaande vervalroutes waargenomen, onder meer vanwege de extreem lange halfwaardetijd, die enkele miljoenen malen groter is dan de leeftijd van het universum.

## Overzicht

| Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | VP | Kernspin | Isotopische verhouding (molfractie) |
| Natuurlijk voorkomen (molfractie) |||
| $^{155}$Ta | 73 | 82 | 154,97459(54) | 13(4) µs | | | (11/2$^−$) | |
| $^{156}$Ta | 73 | 83 | 155,97230(43) | 144(24) ms | β$^+$ (95,8%) | $^{156}$Hf | (2$^−$) | |
| $^{156}$Ta | 73 | 83 | 155,97230(43) | 144(24) ms | p (4,2%) | $^{155}$Hf | (2$^−$) | |
| $^{156m}$Ta | 102(7) keV | 102(7) keV | 102(7) keV | 0,36(4) s | p | $^{155}$Hf | 9$^+$ | |
| $^{157}$Ta | 73 | 84 | 156,96819(22) | 10,1(4) ms | α (91%) | $^{153}$Lu | 1/2$^+$ | |
| $^{157}$Ta | 73 | 84 | 156,96819(22) | 10,1(4) ms | β$^+$ (9%) | $^{157}$Hf | 1/2$^+$ | |
| $^{157m1}$Ta | 22(5) keV | 22(5) keV | 22(5) keV | 4,3(1) ms | | | 11/2$^−$ | |
| $^{157m2}$Ta | 1593(9) keV | 1593(9) keV | 1593(9) keV | 1,7(1) ms | α | $^{153}$Lu | (25/2$^−$) | |
| $^{158}$Ta | 73 | 85 | 157,96670(22) | 49(8) ms | α (96%) | $^{154}$Lu | (2$^−$) | |
| $^{158}$Ta | 73 | 85 | 157,96670(22) | 49(8) ms | β$^+$ (4%) | $^{158}$Hf | (2$^−$) | |
| $^{158m}$Ta | 141(9) keV | 141(9) keV | 141(9) keV | 36,0(8) ms | α (93%) | $^{154}$Lu | (9$^+$) | |
| $^{158m}$Ta | 141(9) keV | 141(9) keV | 141(9) keV | 36,0(8) ms | IT | $^{158}$Ta | (9$^+$) | |
| $^{158m}$Ta | 141(9) keV | 141(9) keV | 141(9) keV | 36,0(8) ms | β$^+$ | $^{158}$Hf | (9$^+$) | |
| $^{159}$Ta | 73 | 86 | 158,963018(22) | 1,04(9) s | β$^+$ (66%) | $^{159}$Hf | (1/2$^+$) | |
| $^{159}$Ta | 73 | 86 | 158,963018(22) | 1,04(9) s | α (34%) | $^{155}$Lu | (1/2$^+$) | |
| $^{159m}$Ta | 64(5) keV | 64(5) keV | 64(5) keV | 514(9) ms | α (56%) | $^{155}$Lu | (11/2$^−$) | |
| $^{159m}$Ta | 64(5) keV | 64(5) keV | 64(5) keV | 514(9) ms | β$^+$ (44%) | $^{159}$Hf | (11/2$^−$) | |
| $^{160}$Ta | 73 | 87 | 159,96149(10) | 1,70(20) s | α | $^{156}$Lu | 2$^−$ | |
| $^{160}$Ta | 73 | 87 | 159,96149(10) | 1,70(20) s | β$^+$ | $^{160}$Hf | 2$^−$ | |
| $^{160m}$Ta | 310(90) keV | 310(90) keV | 310(90) keV | 1,55(4) s | β$^+$ (66%) | $^{160}$Hf | 9$^+$ | |
| $^{160m}$Ta | 310(90) keV | 310(90) keV | 310(90) keV | 1,55(4) s | α (34%) | $^{156}$Lu | 9$^+$ | |
| $^{161}$Ta | 73 | 88 | 160,95842(6) | 3 s | β$^+$ (95%) | $^{161}$Hf | 1/2$^+$ | |
| $^{161}$Ta | 73 | 88 | 160,95842(6) | 3 s | α (5%) | $^{157}$Lu | 1/2$^+$ | |
| $^{161m}$Ta | 50(50) keV | 50(50) keV | 50(50) keV | 2,89(12) s | | | 11/2$^−$ | |
| $^{162}$Ta | 73 | 89 | 161,95729(6) | 3,57(12) s | β$^+$ (99,92%) | $^{162}$Hf | 3$^+$ | |
| $^{162}$Ta | 73 | 89 | 161,95729(6) | 3,57(12) s | α (0,073%) | $^{158}$Lu | 3$^+$ | |
| $^{163}$Ta | 73 | 90 | 162,95433(4) | 10,6(18) s | β$^+$ (99,8%) | $^{163}$Hf | 1/2$^+$ | |
| $^{163}$Ta | 73 | 90 | 162,95433(4) | 10,6(18) s | α (0,2%) | $^{159}$Lu | 1/2$^+$ | |
| $^{164}$Ta | 73 | 91 | 163,95353(3) | 14,2(3) s | β$^+$ | $^{164}$Hf | (3$^+$) | |
| $^{165}$Ta | 73 | 92 | 164,950773(19) | 31,0(15) s | β$^+$ | $^{165}$Hf | 5/2$^−$ | |
| $^{165m}$Ta | 60(30) keV | 60(30) keV | 60(30) keV | | | | 9/2$^−$ | |
| $^{166}$Ta | 73 | 93 | 165,95051(3) | 34,4(5) s | β$^+$ | $^{166}$Hf | 2$^+$ | |
| $^{167}$Ta | 73 | 94 | 166,94809(3) | 1,33(7) min | β$^+$ | $^{167}$Hf | (3/2$^+$) | |
| $^{168}$Ta | 73 | 95 | 167,94805(3) | 2,0(1) min | β$^+$ | $^{168}$Hf | (2$^−$, 3$^+$) | |
| $^{169}$Ta | 73 | 96 | 168,94601(3) | 4,9(4) min | β$^+$ | $^{169}$Hf | (5/2$^+$) | |
| $^{17}$Ta | 73 | 97 | 169,94618(3) | 6,76(6) min | β$^+$ | $^{170}$Hf | (3$^+$) | |
| $^{171}$Ta | 73 | 98 | 170,94448(3) | 23,3(3) min | β$^+$ | $^{171}$Hf | (5/2$^−$) | |
| $^{172}$Ta | 73 | 99 | 171,94490(3) | 36,8(3) min | β$^+$ | $^{172}$Hf | (3$^+$) | |
| $^{173}$Ta | 73 | 100 | 172,94375(3) | 3,14(13) uur | β$^+$ | $^{173}$Hf | 5/2$^−$ | |
| $^{174}$Ta | 73 | 101 | 173,94445(3) | 1,14(8) uur | β$^+$ | $^{174}$Hf | 3$^+$ | |
| $^{175}$Ta | 73 | 102 | 174,94374(3) | 10,5(2) uur | β$^+$ | $^{175}$Hf | 7/2$^+$ | |
| $^{176}$Ta | 73 | 103 | 175,94486(3) | 8,09(5) uur | β$^+$ | $^{176}$Hf | 1$^−$ | |
| $^{176m1}$Ta | 103,0(10) keV | 103,0(10) keV | 103,0(10) keV | 1,1(1) ms | IT | $^{176}$Ta | | |
| $^{176m2}$Ta | 1372,6(11)$^+$X keV | 1372,6(11)$^+$X keV | 1372,6(11)$^+$X keV | 3,8(4) µs | | | (14$^−$) | |
| $^{176m3}$Ta | 2820(50) keV | 2820(50) keV | 2820(50) keV | 0,97(7) ms | | | (20$^−$) | |
| $^{177}$Ta | 73 | 104 | 176,944472(4) | 56,56(6) uur | β$^+$ | $^{177}$Hf | 7/2$^+$ | |
| $^{177m1}$Ta | 73,36(15) keV | 73,36(15) keV | 73,36(15) keV | 410(7) ns | | | 9/2$^−$ | |
| $^{177m2}$Ta | 186,15(6) keV | 186,15(6) keV | 186,15(6) keV | 3,62(10) µs | | | 5/2$^−$ | |
| $^{177m3}$Ta | 1355,01(19) keV | 1355,01(19) keV | 1355,01(19) keV | 5,31(25) µs | | | 21/2$^−$ | |
| $^{177m4}$Ta | 4656,3(5) keV | 4656,3(5) keV | 4656,3(5) keV | 133(4) µs | | | 49/2$^−$ | |
| $^{178}$Ta | 73 | 105 | 177,945778(16) | 9,31(3) min | β$^+$ | $^{178}$Hf | 1$^+$ | |
| $^{178m1}$Ta | 100(50) keV | 100(50) keV | 100(50) keV | 2,36(8) uur | β$^+$ | $^{178}$Hf | 7$^−$ | |
| $^{178m2}$Ta | 1570(50) keV | 1570(50) keV | 1570(50) keV | 59(3) ms | | | (15$^−$) | |
| $^{178m3}$Ta | 3000(50) keV | 3000(50) keV | 3000(50) keV | 290(12) ms | | | (21$^−$) | |
| $^{179}$Ta | 73 | 106 | 178,9459295(23) | 1,82(3) jaar | EV | $^{179}$Hf | 7/2$^+$ | |
| $^{179m1}$Ta | 30,7(1) keV | 30,7(1) keV | 30,7(1) keV | 1,42(8) µs | | | 9/2$^−$ | |
| $^{179m2}$Ta | 520,23(18) keV | 520,23(18) keV | 520,23(18) keV | 335(45) ns | | | 1/2$^+$ | |
| $^{179m3}$Ta | 1252,61(23) keV | 1252,61(23) keV | 1252,61(23) keV | 322(16) ns | | | (21/2$^−$) | |
| $^{179m4}$Ta | 1317,3(4) keV | 1317,3(4) keV | 1317,3(4) keV | 9,0(2) ms | IT | $^{179}$Ta | (25/2$^+$) | |
| $^{179m5}$Ta | 1327,9(4) keV | 1327,9(4) keV | 1327,9(4) keV | 1,6(4) µs | | | (23/2$^−$) | |
| $^{179m6}$Ta | 2639,3(5) keV | 2639,3(5) keV | 2639,3(5) keV | 54,1(17) ms | | | (37/2$^+$) | |
| $^{180}$Ta | 73 | 107 | 179,9474648(24) | 8,152(6) uur | EV (86%) | $^{180}$Hf | 1$^+$ | |
| $^{180}$Ta | 73 | 107 | 179,9474648(24) | 8,152(6) uur | β$^−$ (14%) | $^{180}$W | 1$^+$ | |
| $^{180m1}$Ta | 77,1(8) keV | 77,1(8) keV | 77,1(8) keV | stabiel | stabiel | stabiel | 9$^−$ | 1,2(2) × 10$^{−4}$ |
| $^{180m2}$Ta | 1452,40(18) keV | 1452,40(18) keV | 1452,40(18) keV | 31,2(14) µs | | | 15$^−$ | |
| $^{180m3}$Ta | 3679,0(11) keV | 3679,0(11) keV | 3679,0(11) keV | 2,0(5) µs | | | (22$^−$) | |
| $^{180m4}$Ta | 4171,0$^+$X keV | 4171,0$^+$X keV | 4171,0$^+$X keV | 17(5) µs | | | (23, 24, 25) | |
| $^{181}$Ta | 73 | 108 | 180,9479958(19) | stabiel | stabiel | stabiel | 7/2$^+$ | 0,99988(2) |
| $^{181m1}$Ta | 6,238(20) keV | 6,238(20) keV | 6,238(20) keV | 6,05(12) µs | | | 9/2$^−$ | |
| $^{181m2}$Ta | 615,21(3) keV | 615,21(3) keV | 615,21(3) keV | 18(1) µs | | | 1/2$^+$ | |
| $^{181m3}$Ta | 1485(3) keV | 1485(3) keV | 1485(3) keV | 25(2) µs | | | 21/2$^−$ | |
| $^{181m4}$Ta | 2230(3) keV | 2230(3) keV | 2230(3) keV | 210(20) µs | | | 29/2$^−$ | |
| $^{182}$Ta | 73 | 109 | 181,9501518(19) | 114,43(3) dagen | β$^−$ | $^{182}$W | 3$^−$ | |
| $^{182m1}$Ta | 16,263(3) keV | 16,263(3) keV | 16,263(3) keV | 283(3) ms | IT | $^{182}$Ta | 5$^+$ | |
| $^{182m2}$Ta | 519,572(18) keV | 519,572(18) keV | 519,572(18) keV | 15,84(10) min | | | 10$^−$ | |
| $^{183}$Ta | 73 | 110 | 182,9513726(19) | 5,1(1) dagen | β$^−$ | $^{183}$W | 7/2$^+$ | |
| $^{183m}$Ta | 73,174(12) keV | 73,174(12) keV | 73,174(12) keV | 107(11) ns | | | 9/2$^−$ | |
| $^{184}$Ta | 73 | 111 | 183,954008(28) | 8,7(1) uur | β$^−$ | $^{184}$W | (5$^−$) | |
| $^{185}$Ta | 73 | 112 | 184,955559(15) | 49,4(15) min | β$^−$ | $^{185}$W | (7/2$^+$) | |
| $^{185m}$Ta | 1308(29) keV | 1308(29) keV | 1308(29) keV | > 1 ms | | | (21/2$^−$) | |
| $^{186}$Ta | 73 | 113 | 185,95855(6) | 10,5(3) min | β$^−$ | $^{186}$W | (2$^−$, 3$^−$) | |
| $^{186m}$Ta | | | | 1,54(5) min | | | | |
| $^{187}$Ta | 73 | 114 | 186,96053(21) | 2 min | β$^−$ | $^{187}$W | 7/2$^+$ | |
| $^{188}$Ta | 73 | 115 | 187,96370(21) | 20 s | β$^−$ | $^{188}$W | | |
| $^{189}$Ta | 73 | 116 | 188,96583(32) | 3 s | | | 7/2$^+$ | |
| $^{190}$Ta | 73 | 117 | 189,96923(43) | 0,3 s | | | | |

## 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
$^{155}$Ta · $^{156}$Ta · $^{156m}$Ta · $^{157}$Ta · $^{157m1}$Ta · $^{157m2}$Ta · $^{158}$Ta · $^{158m}$Ta · $^{159}$Ta · $^{159m}$Ta · $^{160}$Ta · $^{160m}$Ta · $^{161}$Ta · $^{161m}$Ta · $^{162}$Ta · $^{163}$Ta · $^{164}$Ta · $^{165}$Ta · $^{165m}$Ta · $^{166}$Ta · $^{167}$Ta · $^{168}$Ta · $^{169}$Ta · $^{170}$Ta · $^{171}$Ta · $^{172}$Ta · $^{173}$Ta · $^{174}$Ta · $^{175}$Ta · $^{176}$Ta · $^{176m1}$Ta · $^{176m2}$Ta · $^{176m3}$Ta · $^{177}$Ta · $^{177m1}$Ta · $^{177m2}$Ta · $^{177m3}$Ta · $^{177m4}$Ta · $^{178}$Ta · $^{178m1}$Ta · $^{178m2}$Ta · $^{178m3}$Ta · $^{179}$Ta · $^{179m1}$Ta · $^{179m2}$Ta · $^{179m3}$Ta · $^{179m4}$Ta · $^{179m5}$Ta · $^{179m6}$Ta · $^{180}$Ta · $^{180m1}$Ta · $^{180m2}$Ta · $^{180m3}$Ta · $^{180m4}$Ta · $^{181}$Ta · $^{181m1}$Ta · $^{181m2}$Ta · $^{181m3}$Ta · $^{181m4}$Ta · $^{182}$Ta · $^{182m1}$Ta · $^{182m2}$Ta · $^{183}$Ta · $^{183m}$Ta · $^{184}$Ta · $^{185}$Ta · $^{185m}$Ta · $^{186}$Ta · $^{186m}$Ta · $^{187}$Ta · $^{188}$Ta · $^{189}$Ta · $^{190}$Ta · $^{191}$Ta · $^{192}$Ta · $^{193}$Ta · $^{194}$Ta