Indium-122
Properties and data of the isotope 122In.
See also: List of individual Indium isotopes (and general data sources).
General data
Name of the isotope:Indium-122; In-122Symbol:122In or 12249InMass number A:122 (= number of nucleons)Atomic number Z:49 (= number of protons)Neutrons N:73Isotopic mass:121.91028(5) u (atomic weight of Indium-122)Nuclide mass:121.8834011 u (calculated nuclear mass without electrons)Mass excess:-83.57364 MeVMass defect:1.105685436 u (per nucleus)Nuclear binding energy:1029.93934952 MeV (per nucleus)
8.44212582 MeV (average binding energy per nucleon)Separation energy:SN = 5.81(6) MeV (first neutron)
SP = 9.79(5) MeV (first proton)Half-life:1.5(3) sDecay constant λ:0.4620981203733 s-1Specific activity α:2.299851216528 × 10+21 Bq g-1
62158140987.268 Ci g-1Spin and parity:
(nuclear angular momentum)1+Charge radius:4.6534(51) femtometer fmYear of discovery:1963
Radioactive Decay
Half-life T½ = 1.5(3) s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β- | 122Sn | 100 % | 6.37(5) MeV | |
Parent Nuclides
Direct parent isotope is: 122Cd.
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 |
|---|
| 122m1In | 40(60) keV | 10.3(6) s | 5+ |
| 122m2In | 290 keV | 10.8(4) s | (8-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 73) and isobaric (same nucleon number A = 122) with Indium-122. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 73 | Isobar A = 122 |
|---|
| 41 | 114Nb | |
| 42 | 115Mo | |
| 43 | 116Tc | |
| 44 | 117Ru | 122Ru |
| 45 | 118Rh | 122Rh |
| 46 | 119Pd | 122Pd |
| 47 | 120Ag | 122Ag |
| 48 | 121Cd | 122Cd |
| 49 | 122In | 122In |
| 50 | 123Sn | 122Sn |
| 51 | 124Sb | 122Sb |
| 52 | 125Te | 122Te |
| 53 | 126I | 122I |
| 54 | 127Xe | 122Xe |
| 55 | 128Cs | 122Cs |
| 56 | 129Ba | 122Ba |
| 57 | 130La | 122La |
| 58 | 131Ce | 122Ce |
| 59 | 132Pr | 122Pr |
| 60 | 133Nd | |
| 61 | 134Pm | |
| 62 | 135Sm | |
| 63 | 136Eu | |
| 64 | 137Gd | |
| 65 | 138Tb | |
| 66 | 139Dy | |
| 67 | 140Ho | |
External data and identifiers
Last update: 2020-10-17
Perma link: https://www.chemlin.org/isotope/indium-122
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