Lutetium-161
Properties and data of the isotope 161Lu.
See also: List of individual Lutetium isotopes (and general data sources).
General data
Name of the isotope:Lutetium-161; Lu-161Symbol:161Lu or 16171LuMass number A:161 (= number of nucleons)Atomic number Z:71 (= number of protons)Neutrons N:90Isotopic mass:160.94357(3) u (atomic weight of Lutetium-161)Nuclide mass:160.9046245 u (calculated nuclear mass without electrons)Mass excess:-52.56421 MeVMass defect:1.391849712 u (per nucleus)Nuclear binding energy:1296.49965563 MeV (per nucleus)
8.05279289 MeV (average binding energy per nucleon)Separation energy:SN = 10.36(6) MeV (first neutron)
SP = 1.689(29) MeV (first proton)Half-life:77(2) sDecay constant λ:0.0090019114358434 s-1Specific activity α:3.388173667207 × 10+19 Bq g-1
915722612.75886 Ci g-1Spin and parity:
(nuclear angular momentum)1/2+Magnetic dipole moment:μ(μN) = + 0.223(3)Nuclear g-factor:gl = 0.446Charge radius:5.2293(320) femtometer fmYear of discovery:1973
Radioactive Decay
Half-life T½ = 77(2) s respectively 7.7 × 101 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 161Yb | 100 % | 5.28(3) MeV | |
Parent Nuclides
Direct parent isotope is: 161Hf.
Nuclear Isomers
Nuclear isomers or excited states with the activation energy in keV related to the ground state.
| Nuclear Isomer | Excitation Energy | Half-life | Spin |
|---|
| 161mLu | 166+x keV | 7.3(4) ms | (9/2-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 90) and isobaric (same nucleon number A = 161) with Lutetium-161. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 90 | Isobar A = 161 |
|---|
| 50 | 140Sn | |
| 51 | 141Sb | |
| 52 | 142Te | |
| 53 | 143I | |
| 54 | 144Xe | |
| 55 | 145Cs | |
| 56 | 146Ba | |
| 57 | 147La | |
| 58 | 148Ce | |
| 59 | 149Pr | |
| 60 | 150Nd | 161Nd |
| 61 | 151Pm | 161Pm |
| 62 | 152Sm | 161Sm |
| 63 | 153Eu | 161Eu |
| 64 | 154Gd | 161Gd |
| 65 | 155Tb | 161Tb |
| 66 | 156Dy | 161Dy |
| 67 | 157Ho | 161Ho |
| 68 | 158Er | 161Er |
| 69 | 159Tm | 161Tm |
| 70 | 160Yb | 161Yb |
| 71 | 161Lu | 161Lu |
| 72 | 162Hf | 161Hf |
| 73 | 163Ta | 161Ta |
| 74 | 164W | 161W |
| 75 | 165Re | 161Re |
| 76 | 166Os | 161Os |
| 77 | 167Ir | |
| 78 | 168Pt | |
External data and identifiers
Last update: 2020-10-11
Perma link: https://www.chemlin.org/isotope/lutetium-161
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