Isotopes of holmium

Natural holmium (67Ho) contains one observationally stable isotope, 165Ho. The below table lists 36 isotopes spanning 140Ho through 175Ho as well as 33 nuclear isomers. Among the known synthetic radioactive isotopes; the most stable one is 163Ho, with a half-life of 4,570 years. All other radioisotopes have half-lives not greater than 1.117 days in their ground states (although the metastable 166m1Ho has a half-life of about 1,200 years), and most have half-lives under 3 hours.

List of isotopes



 * 140Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 73
 * 139.96854(54)#
 * 6(3) ms
 * 8+#
 * 141Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 74
 * 140.96310(54)#
 * 4.1(3) ms
 * (7/2−)
 * style="text-indent:1em" | 141mHo
 * colspan="3" style="text-indent:2em" | 66(2) keV
 * 6.4(8) μs
 * (1/2+)
 * rowspan=2|142Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 75
 * rowspan=2|141.95977(54)#
 * rowspan=2|400(100) ms
 * β+
 * 142Dy
 * rowspan=2|(6 to 9)
 * rowspan=2|
 * p
 * 141Dy
 * 143Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 76
 * 142.95461(43)#
 * 300# ms [>200 ns]
 * β+
 * 143Dy
 * 11/2−#
 * rowspan=2|144Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2|143.95148(32)#
 * rowspan=2|0.7(1) s
 * β+
 * 144Dy
 * rowspan=2|
 * rowspan=2|
 * β+, p
 * 143Tb
 * 145Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 78
 * 144.94720(32)#
 * 2.4(1) s
 * β+
 * 145Dy
 * (11/2−)
 * style="text-indent:1em" | 145mHo
 * colspan="3" style="text-indent:2em" | 100(100)# keV
 * 100# ms
 * 5/2+#
 * rowspan=2|146Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|145.94464(21)#
 * rowspan=2|3.6(3) s
 * β+
 * 146Dy
 * rowspan=2|(10+)
 * rowspan=2|
 * β+, p (rare)
 * 145Tb
 * rowspan=2|147Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 80
 * rowspan=2|146.94006(3)
 * rowspan=2|5.8(4) s
 * β+
 * 147Dy
 * rowspan=2|(11/2−)
 * rowspan=2|
 * β+, p (rare)
 * 146Tb
 * 148Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 81
 * 147.93772(14)
 * 2.2(11) s
 * β+
 * 148Dy
 * (1+)
 * rowspan=2 style="text-indent:1em" | 148m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 400(100)# keV
 * rowspan=2|9.49(12) s
 * β+ (99.92%)
 * 148Dy
 * rowspan=2|(6)−
 * rowspan=2|
 * β+, p (.08%)
 * 147Tb
 * style="text-indent:1em" | 148m2Ho
 * colspan="3" style="text-indent:2em" | 690(100)# keV
 * 2.35(4) ms
 * (10+)
 * 149Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 82
 * 148.933775(20)
 * 21.1(2) s
 * β+
 * 149Dy
 * (11/2−)
 * style="text-indent:1em" | 149m1Ho
 * colspan="3" style="text-indent:2em" | 48.80(20) keV
 * 56(3) s
 * β+
 * 149Dy
 * (1/2+)
 * style="text-indent:1em" | 149m2Ho
 * colspan="3" style="text-indent:2em" | 7200(350) keV
 * >=100 ns
 * 150Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 83
 * 149.933496(15)
 * 76.8(18) s
 * β+
 * 150Dy
 * 2−
 * style="text-indent:1em" | 150m1Ho
 * colspan="3" style="text-indent:2em" | −10(50) keV
 * 23.3(3) s
 * β+
 * 150Dy
 * (9)+
 * style="text-indent:1em" | 150m2Ho
 * colspan="3" style="text-indent:2em" | ~8000 keV
 * 751 ns
 * rowspan=2|151Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|150.931688(13)
 * rowspan=2|35.2(1) s
 * β+ (78%)
 * 151Dy
 * rowspan=2|11/2(−)
 * rowspan=2|
 * α (22%)
 * 147Tb
 * rowspan=2 style="text-indent:1em" | 151mHo
 * rowspan=2 colspan="3" style="text-indent:2em" | 41.0(2) keV
 * rowspan=2|47.2(10) s
 * α (77%)
 * 147Tb
 * rowspan=2|1/2(+)
 * rowspan=2|
 * β+ (22%)
 * 151Dy
 * rowspan=2|152Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|151.931714(15)
 * rowspan=2|161.8(3) s
 * β+ (88%)
 * 152Dy
 * rowspan=2|2−
 * rowspan=2|
 * α (12%)
 * 148Tb
 * style="text-indent:1em" | 152m1Ho
 * colspan="3" style="text-indent:2em" | 160(1) keV
 * 50.0(4) s
 * 9+
 * style="text-indent:1em" | 152m2Ho
 * colspan="3" style="text-indent:2em" | 3019.59(19) keV
 * 8.4(3) μs
 * 19−
 * rowspan=2|153Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 86
 * rowspan=2|152.930199(6)
 * rowspan=2|2.01(3) min
 * β+ (99.94%)
 * 153Dy
 * rowspan=2|11/2−
 * rowspan=2|
 * α (.05%)
 * 149Tb
 * rowspan=2 style="text-indent:1em" | 153m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 68.7(3) keV
 * rowspan=2|9.3(5) min
 * β+ (99.82%)
 * 153Dy
 * rowspan=2|1/2+
 * rowspan=2|
 * α (.18%)
 * 149Tb
 * style="text-indent:1em" | 153m2Ho
 * colspan="3" style="text-indent:2em" | 2772 keV
 * 229(2) ns
 * (31/2+)
 * rowspan=2|154Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|153.930602(9)
 * rowspan=2|11.76(19) min
 * β+ (99.98%)
 * 154Dy
 * rowspan=2|2−
 * rowspan=2|
 * α (.02%)
 * 150Tb
 * rowspan=3 style="text-indent:1em" | 154mHo
 * rowspan=3 colspan="3" style="text-indent:2em" | 238(30) keV
 * rowspan=3|3.10(14) min
 * β+ (99.99%)
 * 154Dy
 * rowspan=3|8+
 * rowspan=3|
 * α (.001%)
 * 150Tb
 * IT (rare)
 * 154Ho
 * 155Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 88
 * 154.929103(19)
 * 48(1) min
 * β+
 * 155Dy
 * 5/2+
 * style="text-indent:1em" | 155mHo
 * colspan="3" style="text-indent:2em" | 141.97(11) keV
 * 880(80) μs
 * 11/2−
 * 156Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 89
 * 155.92984(5)
 * 56(1) min
 * β+
 * 156Dy
 * 4−
 * rowspan=2 style="text-indent:1em" | 156m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 100(50)# keV
 * rowspan=2|7.8(3) min
 * β+
 * 156Dy
 * rowspan=2|(9+)
 * rowspan=2|
 * IT
 * 156Ho
 * style="text-indent:1em" | 156m2Ho
 * colspan="3" style="text-indent:2em" | 52.4(5) keV
 * 9.5(15) s
 * 1−
 * 157Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 90
 * 156.928256(26)
 * 12.6(2) min
 * β+
 * 157Dy
 * 7/2−
 * rowspan=2|158Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 91
 * rowspan=2|157.928941(29)
 * rowspan=2|11.3(4) min
 * β+ (93%)
 * 158Dy
 * rowspan=2|5+
 * rowspan=2|
 * α (7%)
 * 154Tb
 * rowspan=2 style="text-indent:1em" | 158m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 67.200(10) keV
 * rowspan=2|28(2) min
 * IT (81%)
 * 158Ho
 * rowspan=2|2−
 * rowspan=2|
 * β+ (19%)
 * 158Dy
 * style="text-indent:1em" | 158m2Ho
 * colspan="3" style="text-indent:2em" | 180(70)# keV
 * 21.3(23) min
 * (9+)
 * 159Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 92
 * 158.927712(4)
 * 33.05(11) min
 * β+
 * 159Dy
 * 7/2−
 * style="text-indent:1em" | 159mHo
 * colspan="3" style="text-indent:2em" | 205.91(5) keV
 * 8.30(8) s
 * IT
 * 159Ho
 * 1/2+
 * 160Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 93
 * 159.928729(16)
 * 25.6(3) min
 * β+
 * 160Dy
 * 5+
 * rowspan=2 style="text-indent:1em" | 160m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59.98(3) keV
 * rowspan=2|5.02(5) h
 * IT (65%)
 * 160Ho
 * rowspan=2|2−
 * rowspan=2|
 * β+ (35%)
 * 160Dy
 * style="text-indent:1em" | 160m2Ho
 * colspan="3" style="text-indent:2em" | 197(16) keV
 * 3 s
 * (9+)
 * 161Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 94
 * 160.927855(3)
 * 2.48(5) h
 * EC
 * 161Dy
 * 7/2−
 * style="text-indent:1em" | 161mHo
 * colspan="3" style="text-indent:2em" | 211.16(3) keV
 * 6.76(7) s
 * IT
 * 161Ho
 * 1/2+
 * 162Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 95
 * 161.929096(4)
 * 15.0(10) min
 * β+
 * 162Dy
 * 1+
 * rowspan=2 style="text-indent:1em" | 162mHo
 * rowspan=2 colspan="3" style="text-indent:2em" | 106(7) keV
 * rowspan=2|67.0(7) min
 * IT (62%)
 * 162Ho
 * rowspan=2|6−
 * rowspan=2|
 * β+ (38%)
 * 162Dy
 * 163Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 96
 * 162.9287339(27)
 * 4570(25) y
 * EC
 * 163Dy
 * 7/2−
 * style="text-indent:1em" | 163mHo
 * colspan="3" style="text-indent:2em" | 297.88(7) keV
 * 1.09(3) s
 * IT
 * 163Ho
 * 1/2+
 * rowspan=2|164Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2|163.9302335(30)
 * rowspan=2|29(1) min
 * EC (60%)
 * 164Dy
 * rowspan=2|1+
 * rowspan=2|
 * β− (40%)
 * 164Er
 * style="text-indent:1em" | 164mHo
 * colspan="3" style="text-indent:2em" | 139.77(8) keV
 * 38.0(10) min [37.5(+15−5) min]
 * IT
 * 164Ho
 * 6−
 * 165Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 98
 * 164.9303221(27)
 * colspan=3 align=center|Observationally Stable
 * 7/2−
 * 1.0000
 * 166Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 99
 * 165.9322842(27)
 * 26.83(2) h
 * β−
 * 166Er
 * 0−
 * style="text-indent:1em" | 166m1Ho
 * colspan="3" style="text-indent:2em" | 5.985(18) keV
 * 1200(180) y
 * β−
 * 166Er
 * (7)−
 * style="text-indent:1em" | 166m2Ho
 * colspan="3" style="text-indent:2em" | 190.9052(20) keV
 * 185(15) μs
 * 3+
 * 167Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 100
 * 166.933133(6)
 * 3.003(18) h
 * β−
 * 167Er
 * 7/2−
 * style="text-indent:1em" | 167mHo
 * colspan="3" style="text-indent:2em" | 259.34(11) keV
 * 6.0(10) μs
 * 3/2+
 * 168Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 101
 * 167.93552(3)
 * 2.99(7) min
 * β−
 * 168Er
 * 3+
 * rowspan=2 style="text-indent:1em" | 168m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59(1) keV
 * rowspan=2|132(4) s
 * IT (99.5%)
 * 168Ho
 * rowspan=2|(6+)
 * rowspan=2|
 * β− (.5%)
 * 168Er
 * style="text-indent:1em" | 168m2Ho
 * colspan="3" style="text-indent:2em" | 143.4(2) keV
 * >4 μs
 * (1)−
 * style="text-indent:1em" | 168m3Ho
 * colspan="3" style="text-indent:2em" | 192.6(2) keV
 * 108(11) ns
 * 1+
 * 169Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 102
 * 168.936872(22)
 * 4.72(10) min
 * β−
 * 169Er
 * 7/2−
 * 170Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 103
 * 169.93962(5)
 * 2.76(5) min
 * β−
 * 170Er
 * 6+#
 * style="text-indent:1em" | 170mHo
 * colspan="3" style="text-indent:2em" | 120(70) keV
 * 43(2) s
 * β−
 * 170Er
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * EC (60%)
 * 164Dy
 * rowspan=2|1+
 * rowspan=2|
 * β− (40%)
 * 164Er
 * style="text-indent:1em" | 164mHo
 * colspan="3" style="text-indent:2em" | 139.77(8) keV
 * 38.0(10) min [37.5(+15−5) min]
 * IT
 * 164Ho
 * 6−
 * 165Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 98
 * 164.9303221(27)
 * colspan=3 align=center|Observationally Stable
 * 7/2−
 * 1.0000
 * 166Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 99
 * 165.9322842(27)
 * 26.83(2) h
 * β−
 * 166Er
 * 0−
 * style="text-indent:1em" | 166m1Ho
 * colspan="3" style="text-indent:2em" | 5.985(18) keV
 * 1200(180) y
 * β−
 * 166Er
 * (7)−
 * style="text-indent:1em" | 166m2Ho
 * colspan="3" style="text-indent:2em" | 190.9052(20) keV
 * 185(15) μs
 * 3+
 * 167Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 100
 * 166.933133(6)
 * 3.003(18) h
 * β−
 * 167Er
 * 7/2−
 * style="text-indent:1em" | 167mHo
 * colspan="3" style="text-indent:2em" | 259.34(11) keV
 * 6.0(10) μs
 * 3/2+
 * 168Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 101
 * 167.93552(3)
 * 2.99(7) min
 * β−
 * 168Er
 * 3+
 * rowspan=2 style="text-indent:1em" | 168m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59(1) keV
 * rowspan=2|132(4) s
 * IT (99.5%)
 * 168Ho
 * rowspan=2|(6+)
 * rowspan=2|
 * β− (.5%)
 * 168Er
 * style="text-indent:1em" | 168m2Ho
 * colspan="3" style="text-indent:2em" | 143.4(2) keV
 * >4 μs
 * (1)−
 * style="text-indent:1em" | 168m3Ho
 * colspan="3" style="text-indent:2em" | 192.6(2) keV
 * 108(11) ns
 * 1+
 * 169Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 102
 * 168.936872(22)
 * 4.72(10) min
 * β−
 * 169Er
 * 7/2−
 * 170Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 103
 * 169.93962(5)
 * 2.76(5) min
 * β−
 * 170Er
 * 6+#
 * style="text-indent:1em" | 170mHo
 * colspan="3" style="text-indent:2em" | 120(70) keV
 * 43(2) s
 * β−
 * 170Er
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * 7/2−#
 * 7/2−#