Niobium-91
Properties and data of the isotope 91Nb.
See also: List of individual Niobium isotopes (and general data sources).
General data
Name of the isotope:Niobium-91; Nb-91Symbol:91Nb or 9141NbMass number A:91 (= number of nucleons)Atomic number Z:41 (= number of protons)Neutrons N:50Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.219512195122 (= neutron-proton ratio)Neutron excess (N-Z):9Isotopic mass:90.906990(3) u (atomic weight of Niobium-91)Nuclide mass:90.8844992 u (calculated nuclear mass without electrons)Mass excess:-86.63826 MeVMass defect:0.84708211200001 u (per nucleus)Nuclear binding energy:789.05190484 MeV (per nucleus)
8.67090005 MeV (average binding energy per nucleon)Separation energy:SN = 12.048(4) MeV (first neutron)
SP = 5.1544(29) MeV (first proton)Half-life:680(130) aDecay constant λ:3.232962595895 × 10-11 s-1Specific activity α:216326179415.42 Bq g-1
5.8466534977141 Ci g-1Spin and parity:
(nuclear angular momentum)9/2+Magnetic dipole moment:μ(μN) = +6.513(3)Quadrupole moment Q:-0.25(3) barn (100 fm2)Nuclear g-factor:gl = 1.4473333333333Charge radius:4.2878(40) femtometer fmYear of discovery:1951
Radioactive Decay
Half-life T½ = 680(130) a respectively 2.144 × 1010 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 91Zr | 100 % | 1.2576(29) MeV | |
Parent Nuclides
Direct parent isotope is: 91Mo.
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 |
|---|
| 91m1Nb | 104.60(5) keV | 60.86(22) d | 1/2- |
| 91m2Nb | 2034.42(20) keV | 3.76(12) μs | (17/2-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 50) and isobaric (same nucleon number A = 91) with Niobium-91. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 50 | Isobar A = 91 |
|---|
| 28 | 78Ni | |
| 29 | 79Cu | |
| 30 | 80Zn | |
| 31 | 81Ga | |
| 32 | 82Ge | |
| 33 | 83As | 91As |
| 34 | 84Se | 91Se |
| 35 | 85Br | 91Br |
| 36 | 86Kr | 91Kr |
| 37 | 87Rb | 91Rb |
| 38 | 88Sr | 91Sr |
| 39 | 89Y | 91Y |
| 40 | 90Zr | 91Zr |
| 41 | 91Nb | 91Nb |
| 42 | 92Mo | 91Mo |
| 43 | 93Tc | 91Tc |
| 44 | 94Ru | 91Ru |
| 45 | 95Rh | 91Rh |
| 46 | 96Pd | 91Pd |
| 47 | 97Ag | |
| 48 | 98Cd | |
| 49 | 99In | |
| 50 | 100Sn | |
External data and identifiers
Last update: 2020-10-15
Perma link: https://www.chemlin.org/isotope/niobium-91
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