Promethium-161
Properties and data of the isotope 161Pm.
See also: list of Promethium isotopes.
General data
Name of the isotope:Promethium-161; Pm-161Symbol:161Pm or 16161PmMass number A:161 (= number of nucleons)Atomic number Z:61 (= number of protons)Neutrons N:100Isotopic mass:160.94607(32) u (atomic weight of Promethium-161)Nuclide mass:160.9126092 u (calculated nuclear mass without electrons)Mass excess:-50.23547 MeVMass defect:1.397748552 u (per nucleus)Nuclear binding energy:1301.9943897 MeV (per nucleus)
8.08692168 MeV (average binding energy per nucleon)Separation energy:SN = 5.30(36) MeV (first neutron)
SP = 10.39(42) MeV (first proton)Half-life:1.05(15) sDecay constant λ:0.66014017196185 s-1Specific activity α:2.484660689285 × 10+21 Bq g-1
67152991602.316 Ci g-1Spin and parity:
(nuclear angular momentum)(5/2-)Year of discovery:2012
Radioactive Decay
Half-life T½ = 1.05(15) s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
---|
β- | 161Sm | 100 % | 6.44(30) MeV | |
β-, n | 160Sm | ? | 1.93(30) MeV | |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 100) and isobaric (same nucleon number A = 161) with Promethium-161. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
Z | Isotone N = 100 | Isobar A = 161 |
59 | 159Pr | |
60 | 160Nd | 161Nd |
61 | 161Pm | 161Pm |
62 | 162Sm | 161Sm |
63 | 163Eu | 161Eu |
64 | 164Gd | 161Gd |
65 | 165Tb | 161Tb |
66 | 166Dy | 161Dy |
67 | 167Ho | 161Ho |
68 | 168Er | 161Er |
69 | 169Tm | 161Tm |
70 | 170Yb | 161Yb |
71 | 171Lu | 161Lu |
72 | 172Hf | 161Hf |
73 | 173Ta | 161Ta |
74 | 174W | 161W |
75 | 175Re | 161Re |
76 | 176Os | 161Os |
77 | 177Ir | |
78 | 178Pt | |
79 | 179Au | |
80 | 180Hg | |
81 | 181Tl | |
82 | 182Pb | |
External data and identifiers
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/promethium-161
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