# Isotopen van terbium

Het chemisch element terbium (Tb), met een atoommassa van 158,92535(2) u, bezit 1 stabiele isotoop: $^{159}$Tb, die theoretisch gezien in staat is om spontane splijting te ondergaan. Het is tevens de enige in de natuur voorkomende isotoop van dit element, waardoor het valt onder de mononuclidische elementen. De 35 radio-isotopen zijn onstabiel en hebben een relatief korte halfwaardetijd (de meeste minder dan een seconde).
De kortstlevende isotoop van terbium is $^{135}$Tb, met een halfwaardetijd van ongeveer 0,94 milliseconden. De langstlevende is $^{158}$Tb, met een halfwaardetijd van 180 jaar.

## Overzicht

| Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | VP | Kernspin | Isotopische verhouding (molfractie) |
| Natuurlijk voorkomen (molfractie) |||
| $^{135}$Tb | 65 | 70 | | 0,94 ms | | | (7/2$^−$) | |
| $^{136}$Tb | 65 | 71 | 135,96138(64) | 0,2 s | | | | |
| $^{137}$Tb | 65 | 72 | 136,95598(64) | 600 ms | | | 11/2$^−$ | |
| $^{138}$Tb | 65 | 73 | 137,95316(43) | 800 ms | β$^+$ | $^{138}$Gd | | |
| $^{138}$Tb | 65 | 73 | 137,95316(43) | 800 ms | p | $^{137}$Gd | | |
| $^{139}$Tb | 65 | 74 | 138,94829(32) | 1,6(2) s | β$^+$ | $^{139}$Gd | 11/2$^−$ | |
| $^{140}$Tb | 65 | 75 | 139,94581(86) | 2,4(2) s | β$^+$ (99,74%) | $^{140}$Gd | 5 | |
| $^{140}$Tb | 65 | 75 | 139,94581(86) | 2,4(2) s | β$^+$, p (0,26%) | $^{139}$Eu | 5 | |
| $^{141}$Tb | 65 | 76 | 140,94145(11) | 3,5(2) s | β$^+$ | $^{141}$Gd | (5/2$^−$) | |
| $^{141m}$Tb | 0(200) keV | 0(200) keV | 0(200) keV | 7,9(6) s | β$^+$ | $^{141}$Gd | 11/2$^−$ | |
| $^{142}$Tb | 65 | 77 | 141,93874(32) | 597(17) ms | β$^+$ | $^{142}$Gd | 1$^+$ | |
| $^{142}$Tb | 65 | 77 | 141,93874(32) | 597(17) ms | β$^+$, p | $^{141}$Eu | 1$^+$ | |
| $^{142m1}$Tb | 280,2(10) keV | 280,2(10) keV | 280,2(10) keV | 303(17) ms | IT (99,5%) | $^{142}$Tb | (5$^−$) | |
| $^{142m1}$Tb | 280,2(10) keV | 280,2(10) keV | 280,2(10) keV | 303(17) ms | β$^+$ (0,5%) | $^{142}$Gd | (5$^−$) | |
| $^{142m2}$Tb | 621,4(11) keV | 621,4(11) keV | 621,4(11) keV | 15(4) µs | | | | |
| $^{143}$Tb | 65 | 78 | 142,93512(6) | 12(1) s | β$^+$ | $^{143}$Gd | (11/2$^−$) | |
| $^{143m}$Tb | 0(100) keV | 0(100) keV | 0(100) keV | < 21 s | β$^+$ | $^{143}$Gd | 5/2$^+$ | |
| $^{144}$Tb | 65 | 79 | 143,93305(3) | ± 1 s | β$^+$ | $^{144}$Gd | 1$^+$ | |
| $^{144}$Tb | 65 | 79 | 143,93305(3) | ± 1 s | β$^+$, p (zelden) | $^{143}$Eu | 1$^+$ | |
| $^{144m1}$Tb | 396,9(5) keV | 396,9(5) keV | 396,9(5) keV | 4,25(15) s | IT (66%) | $^{144}$Tb | (6$^−$) | |
| $^{144m1}$Tb | 396,9(5) keV | 396,9(5) keV | 396,9(5) keV | 4,25(15) s | β$^+$ (34%) | $^{144}$Gd | (6$^−$) | |
| $^{144m1}$Tb | 396,9(5) keV | 396,9(5) keV | 396,9(5) keV | 4,25(15) s | β$^+$, p (< 1%) | $^{143}$Eu | (6$^−$) | |
| $^{144m2}$Tb | 476,2(5) keV | 476,2(5) keV | 476,2(5) keV | 2,8(3) µs | | | (8$^−$) | |
| $^{144m3}$Tb | 517,1(5) keV | 517,1(5) keV | 517,1(5) keV | 670(60) ns | | | (9$^+$) | |
| $^{144m4}$Tb | 544,5(6) keV | 544,5(6) keV | 544,5(6) keV | < 300 ns | | | (10$^+$) | |
| $^{145}$Tb | 65 | 80 | 144,92927(6) | 20 min | β$^+$ | $^{145}$Gd | (3/2$^+$) | |
| $^{145m}$Tb | 0(100) keV | 0(100) keV | 0(100) keV | 30,9(7) s | β$^+$ | $^{145}$Gd | (11/2$^−$) | |
| $^{146}$Tb | 65 | 81 | 145,92725(5) | 8(4) s | β$^+$ | $^{146}$Gd | 1$^+$ | |
| $^{146m1}$Tb | 150(100) keV | 150(100) keV | 150(100) keV | 24,1(5) s | β$^+$ | $^{146}$Gd | 5$^−$ | |
| $^{146m2}$Tb | 930(100) keV | 930(100) keV | 930(100) keV | 1,18(2) ms | | | (10$^+$) | |
| $^{147}$Tb | 65 | 82 | 146,924045(13) | 1,64(3) uur | β$^+$ | $^{147}$Gd | 1/2$^+$ | |
| $^{147m}$Tb | 50,6(9) keV | 50,6(9) keV | 50,6(9) keV | 1,87(5) min | β$^+$ | $^{147}$Gd | 11/2$^−$ | |
| $^{148}$Tb | 65 | 83 | 147,924272(15) | 60(1) min | β$^+$ | $^{148}$Gd | 2$^−$ | |
| $^{148m1}$Tb | 90,1(3) keV | 90,1(3) keV | 90,1(3) keV | 2,20(5) min | β$^+$ | $^{148}$Gd | 9$^+$ | |
| $^{148m2}$Tb | 8618,6(10) keV | 8618,6(10) keV | 8618,6(10) keV | 1,310(7) µs | | | (27$^+$) | |
| $^{149}$Tb | 65 | 84 | 148,923246(5) | 4,118(25) uur | β$^+$ (83,3%) | $^{149}$Gd | 1/2$^+$ | |
| $^{149}$Tb | 65 | 84 | 148,923246(5) | 4,118(25) uur | α (16,7%) | $^{145}$Eu | 1/2$^+$ | |
| $^{149m}$Tb | 35,78(13) keV | 35,78(13) keV | 35,78(13) keV | 4,16(4) min | β$^+$ (99,97%) | $^{149}$Gd | 11/2$^−$ | |
| $^{149m}$Tb | 35,78(13) keV | 35,78(13) keV | 35,78(13) keV | 4,16(4) min | α (0,022%) | $^{145}$Eu | 11/2$^−$ | |
| $^{150}$Tb | 65 | 85 | 149,923660(8) | 3,48(16) uur | β$^+$ (99,95%) | $^{150}$Gd | (2$^−$) | |
| $^{150}$Tb | 65 | 85 | 149,923660(8) | 3,48(16) uur | α (0,05%) | $^{146}$Eu | (2$^−$) | |
| $^{150m}$Tb | 457(29) keV | 457(29) keV | 457(29) keV | 5,8(2) min | β$^+$ | $^{150}$Gd | 9$^+$ | |
| $^{150m}$Tb | 457(29) keV | 457(29) keV | 457(29) keV | 5,8(2) min | IT (zelden) | $^{150}$Tb | 9$^+$ | |
| $^{151}$Tb | 65 | 86 | 150,923103(5) | 17,609(1) uur | β$^+$ (99,99%) | $^{151}$Gd | 1/2$^+$ | |
| $^{151}$Tb | 65 | 86 | 150,923103(5) | 17,609(1) uur | α (0,0095%) | $^{147}$Eu | 1/2$^+$ | |
| $^{151m}$Tb | 99,54(6) keV | 99,54(6) keV | 99,54(6) keV | 25(3) s | IT (93,8%) | $^{151}$Tb | (11/2$^−$) | |
| $^{151m}$Tb | 99,54(6) keV | 99,54(6) keV | 99,54(6) keV | 25(3) s | β$^+$ (6,2%) | $^{151}$Gd | (11/2$^−$) | |
| $^{152}$Tb | 65 | 87 | 151,92407(4) | 17,5(1) uur | β$^+$ | $^{152}$Gd | 2$^−$ | |
| $^{152}$Tb | 65 | 87 | 151,92407(4) | 17,5(1) uur | α (7 × 10$^{−7}$%) | $^{148}$Eu | 2$^−$ | |
| $^{152m1}$Tb | 342,15(16) keV | 342,15(16) keV | 342,15(16) keV | 0,96 µs | | | 5$^−$ | |
| $^{152m2}$Tb | 501,74(19) keV | 501,74(19) keV | 501,74(19) keV | 4,2(1) min | IT (78,8%) | $^{152}$Tb | 8$^+$ | |
| $^{152m2}$Tb | 501,74(19) keV | 501,74(19) keV | 501,74(19) keV | 4,2(1) min | β$^+$ (21,2%) | $^{152}$Gd | 8$^+$ | |
| $^{153}$Tb | 65 | 88 | 152,923435(5) | 2,34(1) dagen | β$^+$ | $^{153}$Gd | 5/2$^+$ | |
| $^{153m}$Tb | 163,175(5) keV | 163,175(5) keV | 163,175(5) keV | 186(4) µs | | | 11/2$^−$ | |
| $^{154}$Tb | 65 | 89 | 153,92468(5) | 21,5(4) uur | β$^+$ (99,9%) | $^{154}$Gd | 0$^+$ | |
| $^{154}$Tb | 65 | 89 | 153,92468(5) | 21,5(4) uur | β$^−$ (0,1%) | $^{154}$Dy | 0$^+$ | |
| $^{154m1}$Tb | 12(7) keV | 12(7) keV | 12(7) keV | 9,4(4) uur | β$^+$ (78,2%) | $^{154}$Gd | 3$^−$ | |
| $^{154m1}$Tb | 12(7) keV | 12(7) keV | 12(7) keV | 9,4(4) uur | IT (21,8%) | $^{154}$Tb | 3$^−$ | |
| $^{154m1}$Tb | 12(7) keV | 12(7) keV | 12(7) keV | 9,4(4) uur | β$^−$ (0,1%) | $^{154}$Dy | 3$^−$ | |
| $^{154m2}$Tb | 200(150) keV | 200(150) keV | 200(150) keV | 22,7(5) uur | | | 7$^−$ | |
| $^{154m3}$Tb | 0$^+$Z keV | 0$^+$Z keV | 0$^+$Z keV | 513(42) ns | | | | |
| $^{155}$Tb | 65 | 90 | 154,923505(13) | 5,32(6) d | EV | $^{155}$Gd | 3/2$^+$ | |
| $^{156}$Tb | 65 | 91 | 155,924747(5) | 5,35(10) dagen | β$^+$ | $^{156}$Gd | 3$^−$ | |
| $^{156}$Tb | 65 | 91 | 155,924747(5) | 5,35(10) dagen | β$^−$ (zelden) | $^{156}$Dy | 3$^−$ | |
| $^{156m1}$Tb | 54(3) keV | 54(3) keV | 54(3) keV | 24,4(10) uur | IT | $^{156}$Tb | (7$^−$) | |
| $^{156m2}$Tb | 88,4(2) keV | 88,4(2) keV | 88,4(2) keV | 5,3(2) uur | | | (0$^+$) | |
| $^{157}$Tb | 65 | 92 | 156,9240246(27) | 71(7) jaar | EV | $^{157}$Gd | 3/2$^+$ | |
| $^{158}$Tb | 65 | 93 | 157,9254131(28) | 180(11) jaar | β$^+$ (83,4%) | $^{158}$Gd | 3- | |
| $^{158}$Tb | 65 | 93 | 157,9254131(28) | 180(11) jaar | β$^−$ (16,6%) | $^{158}$Dy | 3- | |
| $^{158m1}$Tb | 110,3(12) keV | 110,3(12) keV | 110,3(12) keV | 10,70(17) s | IT (99,39%) | $^{158}$Tb | 0- | |
| $^{158m1}$Tb | 110,3(12) keV | 110,3(12) keV | 110,3(12) keV | 10,70(17) s | β$^−$ (0,6%) | $^{158}$Dy | 0- | |
| $^{158m1}$Tb | 110,3(12) keV | 110,3(12) keV | 110,3(12) keV | 10,70(17) s | β$^+$ (0,01%) | $^{158}$Gd | 0- | |
| $^{158m2}$Tb | 388,37(15) keV | 388,37(15) keV | 388,37(15) keV | 0,40(4) ms | | | 7$^−$ | |
| $^{159}$Tb | 65 | 94 | 158,9253468(27) | stabiel | stabiel | stabiel | 3/2$^+$ | 1,0000 |
| $^{160}$Tb | 65 | 95 | 159,9271676(27) | 72,3(2) dagen | β$^−$ | $^{160}$Dy | 3$^−$ | |
| $^{161}$Tb | 65 | 96 | 160,9275699(28) | 6,906(19) dagen | β$^−$ | $^{161}$Dy | 3/2$^+$ | |
| $^{162}$Tb | 65 | 97 | 161,92949(4) | 7,60(15) min | β$^−$ | $^{162}$Dy | 1$^−$ | |
| $^{163}$Tb | 65 | 98 | 162,930648(5) | 19,5(3) min | β$^−$ | $^{163}$Dy | 3/2$^+$ | |
| $^{164}$Tb | 65 | 99 | 163,93335(11) | 3,0(1) min | β$^−$ | $^{164}$Dy | (5$^+$) | |
| $^{165}$Tb | 65 | 100 | 164,93488(21) | 2,11(10) min | β$^−$ | $^{165m}$Dy | 3/2$^+$ | |
| $^{166}$Tb | 65 | 101 | 165,93799(11) | 25,6(22) s | β$^−$ | $^{166}$Dy | | |
| $^{167}$Tb | 65 | 102 | 166,94005(43) | 19,4(27) s | β$^−$ | $^{167}$Dy | 3/2$^+$ | |
| $^{168}$Tb | 65 | 103 | 167,94364(54) | 8,2(13) s | β$^−$ | $^{168}$Dy | 4$^−$ | |
| $^{169}$Tb | 65 | 104 | 168,94622(64) | 2 s | β$^−$ | $^{169}$Dy | 3/2$^+$ | |
| $^{170}$Tb | 65 | 105 | 169,95025(75) | 3 s | β$^−$ | $^{170}$Dy | | |
| $^{171}$Tb | 65 | 106 | 170,95330(86) | 500 ms | β$^−$ | $^{171}$Dy | 3/2$^+$ | |

## 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
$^{135}$Tb · $^{136}$Tb · $^{137}$Tb · $^{138}$Tb · $^{139}$Tb · $^{140}$Tb · $^{141}$Tb · $^{141m}$Tb · $^{142}$Tb · $^{142m1}$Tb · $^{142m2}$Tb · $^{143}$Tb · $^{143m}$Tb · $^{144}$Tb · $^{144m1}$Tb · $^{144m2}$Tb · $^{144m3}$Tb · $^{144m4}$Tb · $^{145}$Tb · $^{145m}$Tb · $^{146}$Tb · $^{146m1}$Tb · $^{146m2}$Tb · $^{147}$Tb · $^{147m}$Tb · $^{148}$Tb · $^{148m1}$Tb · $^{148m2}$Tb · $^{149}$Tb · $^{149m}$Tb · $^{150}$Tb · $^{150m}$Tb · $^{151}$Tb · $^{151m}$Tb · $^{152}$Tb · $^{152m1}$Tb · $^{152m2}$Tb · $^{153}$Tb · $^{153m}$Tb · $^{154}$Tb · $^{154m1}$Tb · $^{154m2}$Tb · $^{154m3}$Tb · $^{155}$Tb · $^{156}$Tb · $^{156m1}$Tb · $^{156m2}$Tb · $^{157}$Tb · $^{158}$Tb · $^{158m1}$Tb · $^{158m2}$Tb · $^{159}$Tb · $^{160}$Tb · $^{161}$Tb · $^{162}$Tb · $^{163}$Tb · $^{164}$Tb · $^{165}$Tb · $^{166}$Tb · $^{167}$Tb · $^{168}$Tb · $^{169}$Tb · $^{170}$Tb · $^{171}$Tb · $^{172}$Tb