Isotopes of holmium

Natural holmium (₆₇Ho) contains one observationally stable isotope, ¹⁶⁵Ho. The known isotopes of holmium range from ¹⁴⁰Ho to ¹⁷⁵Ho. The primary decay mode before the stable ¹⁶⁵Ho, is beta plus decay to dysprosium isotopes, and the primary mode after is beta minus decay to erbium isotopes.

Among the synthetic radioactive isotopes the most stable is ¹⁶³Ho with a half-life of 4,570 years, the next most stable is ¹⁶⁶Ho having a half-life of 26.812 hours, and others are under 4 hours. The isomeric nuclide ^166m1Ho, however, has a half-life of 1,133 years, much the longest of the meta states.

Holmium-166 (ground state) has been studied for medical application.

List of isotopes

|-id=Holmium-140 | ¹⁴⁰Ho | style="text-align:right" | 67 | style="text-align:right" | 73 | 139.96853(54)# | 6(3)&nbsp;ms | p | ¹³⁹Dy | 8+# | |-id=Holmium-141 | ¹⁴¹Ho | style="text-align:right" | 67 | style="text-align:right" | 74 | 140.96311(43)# | 4.1(1)&nbsp;ms | p | ¹⁴⁰Dy | (7/2−) | |-id=Holmium-141m | style="text-indent:1em" | ^141mHo | colspan="3" style="text-indent:2em" | 66(2)&nbsp;keV | 7.3(3)&nbsp;μs | p | ¹⁴⁰Dy | (1/2+) | |-id=Holmium-142 | rowspan=3|¹⁴²Ho | rowspan=3 style="text-align:right" | 67 | rowspan=3 style="text-align:right" | 75 | rowspan=3|141.96001(43)# | rowspan=3|400(100)&nbsp;ms | β⁺ | ¹⁴²Dy | rowspan=3|(7−, 8+) | rowspan=3| |- | β⁺, p (?%) | ¹⁴¹Tb |- | p (?%) | ¹⁴¹Dy |-id=Holmium-143 | ¹⁴³Ho | style="text-align:right" | 67 | style="text-align:right" | 76 | 142.95486(32)# | 300#&nbsp;ms<br>[>310&nbsp;ns] | | | 11/2−# | |-id=Holmium-144 | rowspan=2|¹⁴⁴Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 77 | rowspan=2|143.9521097(91) | rowspan=2|0.7(1)&nbsp;s | β⁺ | ¹⁴⁴Dy | rowspan=2|(5−) | rowspan=2| |- | β⁺, p (?%) | ¹⁴³Tb |-id=Holmium-144m | style="text-indent:1em" | ^144mHo | colspan="3" style="text-indent:2em" | 265.3(3)&nbsp;keV | 519(5)&nbsp;ns | IT | ¹⁴⁴Ho | (8+) | |-id=Holmium-145 | ¹⁴⁵Ho | style="text-align:right" | 67 | style="text-align:right" | 78 | 144.9472674(80) | 2.4(1)&nbsp;s | β⁺ | ¹⁴⁵Dy | (11/2−) | |-id=Holmium-146 | rowspan=2|¹⁴⁶Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 79 | rowspan=2|145.9449935(71) | rowspan=2|3.32(22)&nbsp;s | β⁺ | ¹⁴⁶Dy | rowspan=2|(6−) | rowspan=2| |- | β⁺, p (?%) | ¹⁴⁵Tb |-id=Holmium-147 | ¹⁴⁷Ho | style="text-align:right" | 67 | style="text-align:right" | 80 | 146.9401423(54) | 5.8(4)&nbsp;s | β⁺ | ¹⁴⁷Dy | (11/2−) | |-id=Holmium-147m | style="text-indent:1em" | ^147mHo | colspan="3" style="text-indent:2em" | 2687.1(4)&nbsp;keV | 315(30)&nbsp;ns | IT | ¹⁴⁷Ho | (27/2−) | |-id=Holmium-148 | ¹⁴⁸Ho | style="text-align:right" | 67 | style="text-align:right" | 81 | 147.937744(90) | 2.2(11)&nbsp;s | β⁺ | ¹⁴⁸Dy | (1+) | |-id=Holmium-148m1 | rowspan=2 style="text-indent:1em" | ^148m1Ho | rowspan=2 colspan="3" style="text-indent:2em" | 250(100)#&nbsp;keV | rowspan=2|9.49(12)&nbsp;s | β⁺ (99.92%) | ¹⁴⁸Dy | rowspan=2|(5−) | rowspan=2| |- | β⁺, p (0.08%) | ¹⁴⁷Tb |-id=Holmium-148m2 | style="text-indent:1em" | ^148m2Ho | colspan="3" style="text-indent:2em" | 940(100)#&nbsp;keV | 2.36(6)&nbsp;ms | IT | ^148m1Ho | (10)+ | |-id=Holmium-149 | ¹⁴⁹Ho | style="text-align:right" | 67 | style="text-align:right" | 82 | 148.933820(13) | 21.1(2)&nbsp;s | β⁺ | ¹⁴⁹Dy | (11/2−) | |-id=Holmium-149m | style="text-indent:1em" | ^149mHo | colspan="3" style="text-indent:2em" | 48.80(20)&nbsp;keV | 56(3)&nbsp;s | β⁺ | ¹⁴⁹Dy | (1/2+) | |-id=Holmium-150 | ¹⁵⁰Ho | style="text-align:right" | 67 | style="text-align:right" | 83 | 149.933498(15) | 76.8(18)&nbsp;s | β⁺ | ¹⁵⁰Dy | (2)− | |-id=Holmium-150m1 | style="text-indent:1em" | ^150m1Ho | colspan="3" style="text-indent:2em" | 0(50)&nbsp;keV | 23.3(3)&nbsp;s | β⁺ | ¹⁵⁰Dy | (9)+ | |-id=Holmium-150m2 | style="text-indent:1em" | ^150m2Ho | colspan="3" style="text-indent:2em" | 7900(50)&nbsp;keV | 787(36)&nbsp;ns | IT | ¹⁵⁰Ho | (28−) | |-id=Holmium-151 | rowspan=2|¹⁵¹Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 84 | rowspan=2|150.9316982(89) | rowspan=2|35.2(1)&nbsp;s | β⁺ (78%) | ¹⁵¹Dy | rowspan=2|11/2− | rowspan=2| |- | α (22%) | ¹⁴⁷Tb |-id=Holmium-151m | rowspan=2 style="text-indent:1em" | ^151mHo | rowspan=2 colspan="3" style="text-indent:2em" | 41.0(2)&nbsp;keV | rowspan=2|47.2(13)&nbsp;s | α (77%) | ¹⁴⁷Tb | rowspan=2|1/2+ | rowspan=2| |- | β⁺ (23%) | ¹⁵¹Dy |-id=Holmium-152 | rowspan=2|¹⁵²Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 85 | rowspan=2|151.931718(13) | rowspan=2|161.8(3)&nbsp;s | β⁺ (88%) | ¹⁵²Dy | rowspan=2|2− | rowspan=2| |- | α (12%) | ¹⁴⁸Tb |-id=Holmium-152m1 | rowspan=2 style="text-indent:1em" | ^152m1Ho | rowspan=2 colspan="3" style="text-indent:2em" | 160(3)&nbsp;keV | rowspan=2|49.8(2)&nbsp;s | β⁺ (89.2%) | ¹⁵²Dy | rowspan=2|9+ | rowspan=2| |- | α (10.8%) | ¹⁴⁸Tb

|-id=Holmium-152m2 | style="text-indent:1em" | ^152m2Ho | colspan="3" style="text-indent:2em" | 3019.59(19)&nbsp;keV | 8.4(3)&nbsp;μs | IT | ¹⁵²Ho | 19− | |-id=Holmium-153 | rowspan=2|¹⁵³Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 86 | rowspan=2|152.9302067(54) | rowspan=2|2.01(3)&nbsp;min | β⁺ (99.95%) | ¹⁵³Dy | rowspan=2|11/2− | rowspan=2| |- | α (0.051%) | ¹⁴⁹Tb |-id=Holmium-153m1 | rowspan=2 style="text-indent:1em" | ^153m1Ho | rowspan=2 colspan="3" style="text-indent:2em" | 68.7(3)&nbsp;keV | rowspan=2|9.3(5)&nbsp;min | β⁺ (99.82%) | ¹⁵³Dy | rowspan=2|1/2+ | rowspan=2| |- | α (0.18%) | ¹⁴⁹Tb |-id=Holmium-153m2 | style="text-indent:1em" | ^153m2Ho | colspan="3" style="text-indent:2em" | 2772.3(14)&nbsp;keV | 229(2)&nbsp;ns | IT | ¹⁵³Ho | 31/2+ | |-id=Holmium-154 | rowspan=2|¹⁵⁴Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 87 | rowspan=2|153.9306068(88) | rowspan=2|11.76(19)&nbsp;min | β⁺ (99.98%) | ¹⁵⁴Dy | rowspan=2|2− | rowspan=2| |- | α (0.019%) | ¹⁵⁰Tb |-id=Holmium-154m | rowspan=3 style="text-indent:1em" | ^154mHo | rowspan=3 colspan="3" style="text-indent:2em" | 243(28)&nbsp;keV | rowspan=3|3.10(14)&nbsp;min | β⁺ | ¹⁵⁴Dy | rowspan=3|8+ | rowspan=3| |- | α (<0.001%) | ¹⁵⁰Tb |- | IT (rare) | ¹⁵⁴Ho |-id=Holmium-155 | ¹⁵⁵Ho | style="text-align:right" | 67 | style="text-align:right" | 88 | 154.929103(19) | 48(2)&nbsp;min | β⁺ | ¹⁵⁵Dy | 5/2+ | |-id=Holmium-155m | style="text-indent:1em" | ^155mHo | colspan="3" style="text-indent:2em" | 141.87(11)&nbsp;keV | 880(80)&nbsp;μs | IT | ¹⁵⁵Ho | 11/2− | |-id=Holmium-156 | ¹⁵⁶Ho | style="text-align:right" | 67 | style="text-align:right" | 89 | 155.929642(41) | 56(1)&nbsp;min | β⁺ | ¹⁵⁶Dy | 4− | |-id=Holmium-156m1 | style="text-indent:1em" | ^156m1Ho | colspan="3" style="text-indent:2em" | 52.37(30)&nbsp;keV | 9.5(15)&nbsp;s | IT | ¹⁵⁶Ho | 1− | |-id=Holmium-156m2 | rowspan=2 style="text-indent:1em" | ^156m2Ho | rowspan=2 colspan="3" style="text-indent:2em" | 230(50)&nbsp;keV | rowspan=2|7.6(3)&nbsp;min | β⁺ (75%) | ¹⁵⁶Dy | rowspan=2|9+ | rowspan=2| |- | IT (25%) | ¹⁵⁶Ho |-id=Holmium-157 | ¹⁵⁷Ho | style="text-align:right" | 67 | style="text-align:right" | 90 | 156.928252(25) | 12.6(2)&nbsp;min | β⁺ | ¹⁵⁷Dy | 7/2− | |-id=Holmium-158 | ¹⁵⁸Ho | style="text-align:right" | 67 | style="text-align:right" | 91 | 157.928945(29) | 11.3(4)&nbsp;min | β⁺ | ¹⁵⁸Dy | 5+ | |-id=Holmium-158m1 | rowspan=2 style="text-indent:1em" | ^158m1Ho | rowspan=2 colspan="3" style="text-indent:2em" | 67.20(1)&nbsp;keV | rowspan=2|28(2)&nbsp;min | IT (91%) | ¹⁵⁸Ho | rowspan=2|2− | rowspan=2| |- | β⁺ (9%) | ¹⁵⁸Dy |-id=Holmium-158m2 | style="text-indent:1em" | ^158m2Ho | colspan="3" style="text-indent:2em" | 91.595(12)&nbsp;keV | 140(25)&nbsp;ns | IT | ¹⁵⁸Ho | (2−) | |-id=Holmium-158m3 | style="text-indent:1em" | ^158m3Ho | colspan="3" style="text-indent:2em" | 180(70)#&nbsp;keV | 21.3(23)&nbsp;min | β⁺ | ¹⁵⁸Dy | (9+) | |-id=Holmium-159 | ¹⁵⁹Ho | style="text-align:right" | 67 | style="text-align:right" | 92 | 158.9277187(33) | 33.05(11)&nbsp;min | β⁺ | ¹⁵⁹Dy | 7/2− | |-id=Holmium-159m | style="text-indent:1em" | ^159mHo | colspan="3" style="text-indent:2em" | 205.91(5)&nbsp;keV | 8.30(8)&nbsp;s | IT | ¹⁵⁹Ho | 1/2+ | |-id=Holmium-160 | ¹⁶⁰Ho | style="text-align:right" | 67 | style="text-align:right" | 93 | 159.928736(16) | 25.6(3)&nbsp;min | β⁺ | ¹⁶⁰Dy | 5+ | |-id=Holmium-160m1 | rowspan=2 style="text-indent:1em" | ^160m1Ho | rowspan=2 colspan="3" style="text-indent:2em" | 59.98(3)&nbsp;keV | rowspan=2|5.02(5)&nbsp;h | IT (73%) | ¹⁶⁰Ho | rowspan=2|2− | rowspan=2| |- | β⁺ (27%) | ¹⁶⁰Dy |-id=Holmium-160m2 | style="text-indent:1em" | ^160m2Ho | colspan="3" style="text-indent:2em" | 197(16)&nbsp;keV | ~3&nbsp;s | IT | ¹⁶⁰Ho | (9+) | |-id=Holmium-161 | ¹⁶¹Ho | style="text-align:right" | 67 | style="text-align:right" | 94 | 160.9278618(23) | 2.48(5)&nbsp;h | EC | ¹⁶¹Dy | 7/2− | |-id=Holmium-161m | style="text-indent:1em" | ^161mHo | colspan="3" style="text-indent:2em" | 211.15(3)&nbsp;keV | 6.76(7)&nbsp;s | IT | ¹⁶¹Ho | 1/2+ | |-id=Holmium-162 | ¹⁶²Ho | style="text-align:right" | 67 | style="text-align:right" | 95 | 161.9291025(33) | 15.0(10)&nbsp;min | β⁺ | ¹⁶²Dy | 1+ | |-id=Holmium-162m | rowspan=2 style="text-indent:1em" | ^162mHo | rowspan=2 colspan="3" style="text-indent:2em" | 105.87(6)&nbsp;keV | rowspan=2|67.0(7)&nbsp;min | IT (62%) | ¹⁶²Ho | rowspan=2|6− | rowspan=2| |- | β⁺ (38%) | ¹⁶²Dy |-id=Holmium-163 | ¹⁶³Ho | style="text-align:right" | 67 | style="text-align:right" | 96 | 162.92874026(74) | 4570(25)&nbsp;y | EC | ¹⁶³Dy | 7/2− | |-id=Holmium-163m1 | style="text-indent:1em" | ^163m1Ho | colspan="3" style="text-indent:2em" | 297.88(7)&nbsp;keV | 1.09(3)&nbsp;s | IT | ¹⁶³Ho | 1/2+ | |-id=Holmium-163m2 | style="text-indent:1em" | ^163m2Ho | colspan="3" style="text-indent:2em" | 2109.4(4)&nbsp;keV | 800(150)&nbsp;ns | IT | ¹⁶³Ho | (23/2+) | |-id=Holmium-164 | rowspan=2|¹⁶⁴Ho | rowspan=2 style="text-align:right" | 67 | rowspan=2 style="text-align:right" | 97 | rowspan=2|163.9302405(15) | rowspan=2|28.8(5)&nbsp;min | EC (61%) | ¹⁶⁴Dy | rowspan=2|1+ | rowspan=2| |- | β^− (39%) | ¹⁶⁴Er |-id=Holmium-164m | style="text-indent:1em" | ^164mHo | colspan="3" style="text-indent:2em" | 139.78(7)&nbsp;keV | 36.6(3)&nbsp;min | IT | ¹⁶⁴Ho | 6− | |-id=Holmium-165 | ¹⁶⁵Ho | style="text-align:right" | 67 | style="text-align:right" | 98 | 164.93032912(84) | colspan=3 align=center|Observationally Stable | 7/2− | 1.0000 |-id=Holmium-165m1 | style="text-indent:1em" | ^165m1Ho | colspan="3" style="text-indent:2em" | 361.675(11)&nbsp;keV | 1.512(4)&nbsp;μs | IT | ¹⁶⁵Ho | 3/2+ | |-id=Holmium-165m2 | style="text-indent:1em" | ^165m2Ho | colspan="3" style="text-indent:2em" | 715.33(2)&nbsp;keV | <100&nbsp;ns | IT | ¹⁶⁵Ho | 7/2+ | |-id=Holmium-166 | ¹⁶⁶Ho | style="text-align:right" | 67 | style="text-align:right" | 99 | 165.93229121(84) | 26.812(7)&nbsp;h | β^− | ¹⁶⁶Er | 0− | |-id=Holmium-166m1 | style="text-indent:1em" | ^166m1Ho | colspan="3" style="text-indent:2em" | 5.969(12)&nbsp;keV | 1132.6(39)&nbsp;y | β^− | ¹⁶⁶Er | 7− | |-id=Holmium-166m2 | style="text-indent:1em" | ^166m2Ho | colspan="3" style="text-indent:2em" | 190.9021(20)&nbsp;keV | 185(15)&nbsp;μs | IT | ¹⁶⁶Ho | 3+ | |-id=Holmium-167 | ¹⁶⁷Ho | style="text-align:right" | 67 | style="text-align:right" | 100 | 166.9331403(56) | 3.1(1)&nbsp;h | β^− | ¹⁶⁷Er | 7/2− | |-id=Holmium-167m | style="text-indent:1em" | ^167mHo | colspan="3" style="text-indent:2em" | 259.34(11)&nbsp;keV | 6.0(10)&nbsp;μs | IT | ¹⁶⁷Ho | 3/2+ | |-id=Holmium-168 | ¹⁶⁸Ho | style="text-align:right" | 67 | style="text-align:right" | 101 | 167.935524(32) | 2.99(7)&nbsp;min | β^− | ¹⁶⁸Er | 3+ | |-id=Holmium-168m1 | style="text-indent:1em" | ^168m1Ho | colspan="3" style="text-indent:2em" | 59(1)&nbsp;keV | 132(4)&nbsp;s | IT | ¹⁶⁸Ho | (6+) | |-id=Holmium-168m2 | style="text-indent:1em" | ^168m2Ho | colspan="3" style="text-indent:2em" | 143.43(17)&nbsp;keV | >4&nbsp;μs | IT | ¹⁶⁸Ho | (1)− | |-id=Holmium-168m3 | style="text-indent:1em" | ^168m3Ho | colspan="3" style="text-indent:2em" | 192.57(20)&nbsp;keV | 108(11)&nbsp;ns | IT | ¹⁶⁸Ho | 1+ | |-id=Holmium-169 | ¹⁶⁹Ho | style="text-align:right" | 67 | style="text-align:right" | 102 | 168.936880(22) | 4.72(10)&nbsp;min | β^− | ¹⁶⁹Er | 7/2− | |-id=Holmium-169m | style="text-indent:1em" | ^169mHo | colspan="3" style="text-indent:2em" | 1386.2(4)&nbsp;keV | 118(6)&nbsp;μs | IT | ¹⁶⁹Ho | (19/2+) | |-id=Holmium-170 | ¹⁷⁰Ho | style="text-align:right" | 67 | style="text-align:right" | 103 | 169.939627(54) | 2.76(5)&nbsp;min | β^− | ¹⁷⁰Er | (6+) | |-id=Holmium-170m | style="text-indent:1em" | ^170mHo | colspan="3" style="text-indent:2em" | 100(80)&nbsp;keV | 43(2)&nbsp;s | β^− | ¹⁷⁰Er | (1+) | |-id=Holmium-171 | ¹⁷¹Ho | style="text-align:right" | 67 | style="text-align:right" | 104 | 170.94147(64) | 53(2)&nbsp;s | β^− | ¹⁷¹Er | 7/2−# | |-id=Holmium-172 | ¹⁷²Ho | style="text-align:right" | 67 | style="text-align:right" | 105 | 171.94473(21)# | 25(3)&nbsp;s | β^− | ¹⁷²Er | 0+# | |-id=Holmium-173 | ¹⁷³Ho | style="text-align:right" | 67 | style="text-align:right" | 106 | 172.94702(32)# | 7.1(4)&nbsp;s | β^− | ¹⁷³Er | 7/2−# | |-id=Holmium-173m | style="text-indent:1em" | ^173mHo | colspan="3" style="text-indent:2em" | 405(1)&nbsp;keV | 3.7(12)&nbsp;μs | IT | ¹⁷³Ho | 1/2+# | |-id=Holmium-174 | ¹⁷⁴Ho | style="text-align:right" | 67 | style="text-align:right" | 107 | 173.95076(32)# | 3.7(4)&nbsp;s | β^− | ¹⁷⁴Er | (8−) | |-id=Holmium-175 | ¹⁷⁵Ho | style="text-align:right" | 67 | style="text-align:right" | 108 | 174.95352(43)# | 1.88(55)&nbsp;s | β^− | ¹⁷⁵Er | 7/2−# | |-id=Holmium-176 | ¹⁷⁶Ho | style="text-align:right" | 67 | style="text-align:right" | 109 | 175.95771(54)# | 1#&nbsp;s<br>[>300&nbsp;ns] | | | 4+# | |-id=Holmium-177 | ¹⁷⁷Ho | style="text-align:right" | 67 | style="text-align:right" | 110 | 176.96105(54)# | 1#&nbsp;s<br>[>550&nbsp;ns] | β^− | ¹⁷⁷Er | 7/2−# | |-id=Holmium-178 | ¹⁷⁸Ho | style="text-align:right" | 67 | style="text-align:right" | 111 | 177.96551(54)# | 750#&nbsp;ms<br>[>550&nbsp;ns] | | | 2+# |

See also

Daughter products other than holmium

• Isotopes of erbium
• Isotopes of dysprosium
• Isotopes of terbium

References

• Isotope masses from:
• Isotopic compositions and standard atomic masses from:
• Half-life, spin, and isomer data selected from the following sources.