ホルミウム(Ho)の同位体のうち天然に生成するものは、安定同位体165Hoのみである。人工の放射性同位体も知られ、最も安定な163Hoの半減期は4570年である。その他は全て1.17日以内で、そのほとんどは3時間以内である。核異性体166mHoの半減期は1200年である。
標準原子量は164.93032(2) uである。
一覧
| 同位体核種 | Z(p) | N(n) | 同位体質量 (u) | 半減期 | 核スピン数 | 天然存在比 | 天然存在比
(範囲) |
| 励起エネルギー |
| 140Ho | 67 | 73 | 139.96854(54)# | 6(3) ms | 8+# | | |
| 141Ho | 67 | 74 | 140.96310(54)# | 4.1(3) ms | (7/2-) | | |
| 141mHo | 66(2) keV | 6.4(8) µs | (1/2+) | | |
| 142Ho | 67 | 75 | 141.95977(54)# | 400(100) ms | (6 to 9) | | |
| 143Ho | 67 | 76 | 142.95461(43)# | 300# ms [>200 ns] | 11/2-# | | |
| 144Ho | 67 | 77 | 143.95148(32)# | 0.7(1) s | | | |
| 145Ho | 67 | 78 | 144.94720(32)# | 2.4(1) s | (11/2-) | | |
| 145mHo | 100(100)# keV | 100# ms | 5/2+# | | |
| 146Ho | 67 | 79 | 145.94464(21)# | 3.6(3) s | (10+) | | |
| 147Ho | 67 | 80 | 146.94006(3) | 5.8(4) s | (11/2-) | | |
| 148Ho | 67 | 81 | 147.93772(14) | 2.2(11) s | (1+) | | |
| 148m1Ho | 400(100)# keV | 9.49(12) s | (6)- | | |
| 148m2Ho | 690(100)# keV | 2.35(4) ms | (10+) | | |
| 149Ho | 67 | 82 | 148.933775(20) | 21.1(2) s | (11/2-) | | |
| 149m1Ho | 48.80(20) keV | 56(3) s | (1/2+) | | |
| 149m2Ho | 7200(350) keV | >=100 ns | | | |
| 150Ho | 67 | 83 | 149.933496(15) | 76.8(18) s | 2- | | |
| 150m1Ho | -10(50) keV | 23.3(3) s | (9)+ | | |
| 150m2Ho | ~8000 keV | 751 ns | | | |
| 151Ho | 67 | 84 | 150.931688(13) | 35.2(1) s | 11/2(-) | | |
| 151mHo | 41.0(2) keV | 47.2(10) s | 1/2(+) | | |
| 152Ho | 67 | 85 | 151.931714(15) | 161.8(3) s | 2- | | |
| 152m1Ho | 160(1) keV | 50.0(4) s | 9+ | | |
| 152m2Ho | 3019.59(19) keV | 8.4(3) µs | 19- | | |
| 153Ho | 67 | 86 | 152.930199(6) | 2.01(3) min | 11/2- | | |
| 153m1Ho | 68.7(3) keV | 9.3(5) min | 1/2+ | | |
| 153m2Ho | 2772 keV | 229(2) ns | (31/2+) | | |
| 154Ho | 67 | 87 | 153.930602(9) | 11.76(19) min | 2- | | |
| 154mHo | 238(30) keV | 3.10(14) min | 8+ | | |
| 155Ho | 67 | 88 | 154.929103(19) | 48(1) min | 5/2+ | | |
| 155mHo | 141.97(11) keV | 880(80) µs | 11/2- | | |
| 156Ho | 67 | 89 | 155.92984(5) | 56(1) min | 4- | | |
| 156m1Ho | 100(50)# keV | 7.8(3) min | (9+) | | |
| 156m2Ho | 52.4(5) keV | 9.5(15) s | 1- | | |
| 157Ho | 67 | 90 | 156.928256(26) | 12.6(2) min | 7/2- | | |
| 158Ho | 67 | 91 | 157.928941(29) | 11.3(4) min | 5+ | | |
| 158m1Ho | 67.200(10) keV | 28(2) min | 2- | | |
| 158m2Ho | 180(70)# keV | 21.3(23) min | (9+) | | |
| 159Ho | 67 | 92 | 158.927712(4) | 33.05(11) min | 7/2- | | |
| 159mHo | 205.91(5) keV | 8.30(8) s | 1/2+ | | |
| 160Ho | 67 | 93 | 159.928729(16) | 25.6(3) min | 5+ | | |
| 160m1Ho | 59.98(3) keV | 5.02(5) h | 2- | | |
| 160m2Ho | 197(16) keV | 3 s | (9+) | | |
| 161Ho | 67 | 94 | 160.927855(3) | 2.48(5) h | 7/2- | | |
| 161mHo | 211.16(3) keV | 6.76(7) s | 1/2+ | | |
| 162Ho | 67 | 95 | 161.929096(4) | 15.0(10) min | 1+ | | |
| 162mHo | 106(7) keV | 67.0(7) min | 6- | | |
| 163Ho | 67 | 96 | 162.9287339(27) | 4570(25) a | 7/2- | | |
| 163mHo | 297.88(7) keV | 1.09(3) s | 1/2+ | | |
| 164Ho | 67 | 97 | 163.9302335(30) | 29(1) min | 1+ | | |
| 164mHo | 139.77(8) keV | 38.0(10) min [37.5(+15-5) min] | 6- | | |
| 165Ho | 67 | 98 | 164.9303221(27) | STABLE | 7/2- | 1.0000 | |
| 166Ho | 67 | 99 | 165.9322842(27) | 26.83(2) h | 0- | | |
| 166m1Ho | 5.985(18) keV | 1.20(18)E+3 a | (7)- | | |
| 166m2Ho | 190.9052(20) keV | 185(15) µs | 3+ | | |
| 167Ho | 67 | 100 | 166.933133(6) | 3.003(18) h | 7/2- | | |
| 167mHo | 259.34(11) keV | 6.0(10) µs | 3/2+ | | |
| 168Ho | 67 | 101 | 167.93552(3) | 2.99(7) min | 3+ | | |
| 168m1Ho | 59(1) keV | 132(4) s | (6+) | | |
| 168m2Ho | 143.4(2) keV | >4 µs | (1)- | | |
| 168m3Ho | 192.6(2) keV | 108(11) ns | 1+ | | |
| 169Ho | 67 | 102 | 168.936872(22) | 4.72(10) min | 7/2- | | |
| 170Ho | 67 | 103 | 169.93962(5) | 2.76(5) min | 6+# | | |
| 170mHo | 120(70) keV | 43(2) s | (1+) | | |
| 171Ho | 67 | 104 | 170.94147(64) | 53(2) s | 7/2-# | | |
| 172Ho | 67 | 105 | 171.94482(43)# | 25(3) s | | | |
| 173Ho | 67 | 106 | 172.94729(43)# | 10# s | 7/2-# | | |
| 174Ho | 67 | 107 | 173.95115(54)# | 8# s | | | |
| 175Ho | 67 | 108 | 174.95405(64)# | 5# s | 7/2-# | | |
参考文献
- Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
- Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005).
- Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
- David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.
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