Lead-189
Properties and data of the isotope 189Pb.
See also: List of individual Lead isotopes (and general data sources).
General data
Name of the isotope:Lead-189; Pb-189Symbol:189Pb or 18982PbMass number A:189 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:107Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.3048780487805 (= neutron-proton ratio)Neutron excess (N-Z):25Isotopic mass:188.980844(15) u (atomic weight of Lead-189)Nuclide mass:188.9358656 u (calculated nuclear mass without electrons)Mass excess:-17.8437 MeVMass defect:1.587954636 u (per nucleus)Nuclear binding energy:1479.17021571 MeV (per nucleus)
7.82629744 MeV (average binding energy per nucleon)Separation energy:SN = 8.100(18) MeV (first neutron)
SP = 2.80(3) MeV (first proton)Half-life:39(8) sDecay constant λ:0.017773004629742 s-1Specific activity α:5.693166882160 × 10+19 Bq g-1
1538693751.9352 Ci g-1Spin and parity:
(nuclear angular momentum)(3/2-)Magnetic dipole moment:μ(μN) = - 1.081(9)Quadrupole moment Q:0.50(18) barn (100 fm2)Nuclear g-factor:gl = -0.72066666666667Charge radius:5.4177(23) femtometer fmYear of discovery:1972
Radioactive Decay
Half-life T½ = 39(8) s respectively 3.9 × 101 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β+ | 189Tl | ca. 100 % | 6.772(16) MeV | |
| α | 185Hg | ≤0.4 % | 5.915(4) MeV | |
Parent Nuclides
Direct parent isotopes are: 189Bi, 193Po.
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 |
|---|
| 189m1Pb | 40(4) keV | 50(3) s | (13/2+) |
| 189m2Pb | 2474.53(18) keV | 22.2 μs | (31/2-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 107) and isobaric (same nucleon number A = 189) with Lead-189. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 107 | Isobar A = 189 |
|---|
| 65 | 172Tb | |
| 66 | 173Dy | |
| 67 | 174Ho | |
| 68 | 175Er | |
| 69 | 176Tm | |
| 70 | 177Yb | |
| 71 | 178Lu | |
| 72 | 179Hf | 189Hf |
| 73 | 180Ta | 189Ta |
| 74 | 181W | 189W |
| 75 | 182Re | 189Re |
| 76 | 183Os | 189Os |
| 77 | 184Ir | 189Ir |
| 78 | 185Pt | 189Pt |
| 79 | 186Au | 189Au |
| 80 | 187Hg | 189Hg |
| 81 | 188Tl | 189Tl |
| 82 | 189Pb | 189Pb |
| 83 | 190Bi | 189Bi |
| 84 | 191Po | 189Po |
| 85 | 192At | 189At |
| 86 | 193Rn | |
External data and identifiers
Last update: 2020-10-22
Perma link: https://www.chemlin.org/isotope/lead-189
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