Indium-125
Properties and data of the isotope 125In.
See also: List of individual Indium isotopes (and general data sources).
General data
Name of the isotope:Indium-125; In-125Symbol:125In or 12549InMass number A:125 (= number of nucleons)Atomic number Z:49 (= number of protons)Neutrons N:76Isotopic mass:124.913605(29) u (atomic weight of Indium-125)Nuclide mass:124.8867261 u (calculated nuclear mass without electrons)Mass excess:-80.47642 MeVMass defect:1.128355184 u (per nucleus)Nuclear binding energy:1051.05608376 MeV (per nucleus)
8.40844867 MeV (average binding energy per nucleon)Separation energy:SN = 7.68(4) MeV (first neutron)
SP = 11.064(27) MeV (first proton)Half-life:2.36(4) sDecay constant λ:0.29370643244065 s-1Specific activity α:1.426404441634 × 10+21 Bq g-1
38551471395.535 Ci g-1Spin and parity:
(nuclear angular momentum)9/2+Magnetic dipole moment:μ(μN) = +5.494(9)Quadrupole moment Q:+ 0.71(4) barn (100 fm2)Nuclear g-factor:gl = 1.2208888888889Charge radius:4.6670(64) femtometer fmYear of discovery:1967
Radioactive Decay
Half-life T½ = 2.36(4) s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β- | 125Sn | 100 % | 5.420(27) MeV | |
Parent Nuclides
Direct parent isotope is: 125Cd.
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 |
|---|
| 125mIn | 360.12(9) keV | 12.2(2) s | 1/2(-) |
| 125m2In | 2009.4(7) keV | 9.4(6) μs | (19/2+) |
| 125m3In | 2161.2(9) keV | 5.0(15) ms | (23/2-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 76) and isobaric (same nucleon number A = 125) with Indium-125. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 76 | Isobar A = 125 |
|---|
| 42 | 118Mo | |
| 43 | 119Tc | |
| 44 | 120Ru | |
| 45 | 121Rh | 125Rh |
| 46 | 122Pd | 125Pd |
| 47 | 123Ag | 125Ag |
| 48 | 124Cd | 125Cd |
| 49 | 125In | 125In |
| 50 | 126Sn | 125Sn |
| 51 | 127Sb | 125Sb |
| 52 | 128Te | 125Te |
| 53 | 129I | 125I |
| 54 | 130Xe | 125Xe |
| 55 | 131Cs | 125Cs |
| 56 | 132Ba | 125Ba |
| 57 | 133La | 125La |
| 58 | 134Ce | 125Ce |
| 59 | 135Pr | 125Pr |
| 60 | 136Nd | 125Nd |
| 61 | 137Pm | |
| 62 | 138Sm | |
| 63 | 139Eu | |
| 64 | 140Gd | |
| 65 | 141Tb | |
| 66 | 142Dy | |
| 67 | 143Ho | |
| 68 | 144Er | |
| 69 | 145Tm | |
External data and identifiers
Last update: 2020-10-17
Perma link: https://www.chemlin.org/isotope/indium-125
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