Indium-120
Properties and data of the isotope 120In.
See also: list of Indium isotopes.
General data
Name of the isotope:Indium-120; In-120Symbol:120In or 12049InMass number A:120 (= number of nucleons)Atomic number Z:49 (= number of protons)Neutrons N:71Isotopic mass:119.90797(4) u (atomic weight of Indium-120)Nuclide mass:119.8810911 u (calculated nuclear mass without electrons)Mass excess:-85.72539 MeVMass defect:1.090665604 u (per nucleus)Nuclear binding energy:1015.94846613 MeV (per nucleus)
8.46623722 MeV (average binding energy per nucleon)Separation energy:SN = 6.10(4) MeV (first neutron)
SP = 9.04(5) MeV (first proton)Half-life:3.08(8) sDecay constant λ:0.22504778589609 s-1Specific activity α:1.138881904943 × 10+21 Bq g-1
30780592025.508 Ci g-1Spin and parity:
(nuclear angular momentum)1+Charge radius:4.6443(42) femtometer fmYear of discovery:1958
Radioactive Decay
Half-life T½ = 3.08(8) s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
---|
β- | 120Sn | 100 % | 5.370(40) MeV | |
Parent Nuclides
Direct parent isotope is: 120Cd.
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 |
---|
120m1In | +x keV | 47.3(5) s | (8-) |
120m2In | 70(60) keV | 46.2(8) s | (5)+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 71) and isobaric (same nucleon number A = 120) with Indium-120. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
Z | Isotone N = 71 | Isobar A = 120 |
40 | 111Zr | |
41 | 112Nb | |
42 | 113Mo | |
43 | 114Tc | 120Tc |
44 | 115Ru | 120Ru |
45 | 116Rh | 120Rh |
46 | 117Pd | 120Pd |
47 | 118Ag | 120Ag |
48 | 119Cd | 120Cd |
49 | 120In | 120In |
50 | 121Sn | 120Sn |
51 | 122Sb | 120Sb |
52 | 123Te | 120Te |
53 | 124I | 120I |
54 | 125Xe | 120Xe |
55 | 126Cs | 120Cs |
56 | 127Ba | 120Ba |
57 | 128La | 120La |
58 | 129Ce | 120Ce |
59 | 130Pr | |
60 | 131Nd | |
61 | 132Pm | |
62 | 133Sm | |
63 | 134Eu | |
64 | 135Gd | |
65 | 136Tb | |
External data and identifiers
Last update: 2020-10-17
Perma link: https://www.chemlin.org/isotope/indium-120
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