Indium-126
Properties and data of the isotope 126In.
See also: List of individual Indium isotopes (and general data sources).
General data
Name of the isotope:Indium-126; In-126Symbol:126In or 12649InMass number A:126 (= number of nucleons)Atomic number Z:49 (= number of protons)Neutrons N:77Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.5714285714286 (= neutron-proton ratio)Neutron excess (N-Z):28Isotopic mass:125.916507(29) u (atomic weight of Indium-126)Nuclide mass:125.8896281 u (calculated nuclear mass without electrons)Mass excess:-77.77323 MeVMass defect:1.1341181 u (per nucleus)Nuclear binding energy:1056.42420544 MeV (per nucleus)
8.38431909 MeV (average binding energy per nucleon)Separation energy:SN = 5.37(4) MeV (first neutron)
SP = 11.714(27) MeV (first proton)Half-life:1.53(1) sDecay constant λ:0.453037372915 s-1Specific activity α:2.182603899607 × 10+21 Bq g-1
58989294583.995 Ci g-1Spin and parity:
(nuclear angular momentum)3(+)Magnetic dipole moment:μ(μN) = + 4.028(11)Quadrupole moment Q:+ 0.49(5) barn (100 fm2)Nuclear g-factor:gl = 1.3426666666667Charge radius:4.6702(68) femtometer fmYear of discovery:1974
Radioactive Decay
Half-life T½ = 1.53(1) s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β- | 126Sn | 100 % | 8.242(27) MeV | |
Parent Nuclides
Direct parent isotope is: 126Cd.
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 |
|---|
| 126mIn | 102(64) keV | 1.64(5) s | (8-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 77) and isobaric (same nucleon number A = 126) with Indium-126. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 77 | Isobar A = 126 |
|---|
| 43 | 120Tc | |
| 44 | 121Ru | |
| 45 | 122Rh | 126Rh |
| 46 | 123Pd | 126Pd |
| 47 | 124Ag | 126Ag |
| 48 | 125Cd | 126Cd |
| 49 | 126In | 126In |
| 50 | 127Sn | 126Sn |
| 51 | 128Sb | 126Sb |
| 52 | 129Te | 126Te |
| 53 | 130I | 126I |
| 54 | 131Xe | 126Xe |
| 55 | 132Cs | 126Cs |
| 56 | 133Ba | 126Ba |
| 57 | 134La | 126La |
| 58 | 135Ce | 126Ce |
| 59 | 136Pr | 126Pr |
| 60 | 137Nd | 126Nd |
| 61 | 138Pm | 126Pm |
| 62 | 139Sm | |
| 63 | 140Eu | |
| 64 | 141Gd | |
| 65 | 142Tb | |
| 66 | 143Dy | |
| 67 | 144Ho | |
| 68 | 145Er | |
| 69 | 146Tm | |
External data and identifiers
Last update: 2020-10-17
Perma link: https://www.chemlin.org/isotope/indium-126
© 1996 - 2026 ChemLin
