Rubidium-84
Properties and data of the isotope 84Rb.
See also: List of individual Rubidium isotopes (and general data sources).
General data
Name of the isotope:Rubidium-84; Rb-84Symbol:84Rb or 8437RbMass number A:84 (= number of nucleons)Atomic number Z:37 (= number of protons)Neutrons N:47Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.2702702702703 (= neutron-proton ratio)Neutron excess (N-Z):10Isotopic mass:83.9143752(24) u (atomic weight of Rubidium-84)Nuclide mass:83.8940785 u (calculated nuclear mass without electrons)Mass excess:-79.75899 MeVMass defect:0.78240203600001 u (per nucleus)Nuclear binding energy:728.80280212 MeV (per nucleus)
8.67622383 MeV (average binding energy per nucleon)Separation energy:SN = 8.760(3) MeV (first neutron)
SP = 7.0573(22) MeV (first proton)Half-life:32.82(7) dDecay constant λ:2.444404878743 × 10-7 s-1Specific activity α:1.773560301025 × 10+15 Bq g-1
47934.062189873 Ci g-1Spin and parity:
(nuclear angular momentum)2-Magnetic dipole moment:μ(μN) = - 1.325(2)Quadrupole moment Q:- 0.015(35) barn (100 fm2)Nuclear g-factor:gl = -0.6625Charge radius:4.1999(23) femtometer fmYear of discovery:1947
Radioactive Decay
Half-life T½ = 32.82(7) d respectively 2.835648 × 106 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 84Kr | 96.1(20) % | 2.6804(22) MeV | |
| β- | 84Sr | 3.9(20) % | 0.8906(23) MeV | |
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 |
|---|
| 84mRb | 463.59(8) keV | 20.26(4) min | 6- |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 47) and isobaric (same nucleon number A = 84) with Rubidium-84. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 47 | Isobar A = 84 |
|---|
| 26 | 73Fe | |
| 27 | 74Co | |
| 28 | 75Ni | |
| 29 | 76Cu | |
| 30 | 77Zn | 84Zn |
| 31 | 78Ga | 84Ga |
| 32 | 79Ge | 84Ge |
| 33 | 80As | 84As |
| 34 | 81Se | 84Se |
| 35 | 82Br | 84Br |
| 36 | 83Kr | 84Kr |
| 37 | 84Rb | 84Rb |
| 38 | 85Sr | 84Sr |
| 39 | 86Y | 84Y |
| 40 | 87Zr | 84Zr |
| 41 | 88Nb | 84Nb |
| 42 | 89Mo | 84Mo |
| 43 | 90Tc | |
| 44 | 91Ru | |
| 45 | 92Rh | |
| 46 | 93Pd | |
| 47 | 94Ag | |
| 48 | 95Cd | |
| 49 | 96In | |
External data and identifiers
Last update: 2020-10-14
Perma link: https://www.chemlin.org/isotope/rubidium-84
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