Tellurium-123
Properties and data of the isotope 123Te.
See also: List of individual Tellurium isotopes (and general data sources).
General data
Name of the isotope:Tellurium-123; Te-123Symbol:123Te or 12352TeMass number A:123 (= number of nucleons)Atomic number Z:52 (= number of protons)Neutrons N:71Isotopic mass:122.90427(1) u (atomic weight of Tellurium-123)Nuclide mass:122.8757456 u (calculated nuclear mass without electrons)Mass excess:-89.17192 MeVMass defect:1.1178407 u (per nucleus)Nuclear binding energy:1041.26190501 MeV (per nucleus)
8.46554394 MeV (average binding energy per nucleon)Separation energy:SN = 6.92901(8) MeV (first neutron)
SP = 8.1258(21) MeV (first proton)Half-life:9.2 × 1016 aDecay constant λ:2.389081838009 × 10-25 s-1Specific activity α:0.0011792940454435 Bq g-1
3.187281203901 × 10-14 Ci g-1Spin and parity:
(nuclear angular momentum)1/2+Magnetic dipole moment:μ(μN) = -0.7358(3)Charge radius:4.7117(35) femtometer fmYear of discovery:1932
Radioactive Decay
Half-life T½ = 9.2 × 1016 a respectively 2.901312 × 1024 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC | 123Sb | 100 % | 0.0519(21) MeV | |
Parent Nuclides
Direct parent isotope is: 123I.
Occurrence
Comparison of the natural Tellurium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
| | Atomic Mass ma | Quantity | Half-life | Spin |
|---|
Tellurium
Isotopic mixture | 127.60 u | 100 % | | |
| Isotope 120Te | 119.90406(2) u | 0.09(1) % | stable | 0+ |
| Isotope 122Te | 121.90304(1) u | 2.55(12) % | stable | 0+ |
| Isotope 123Te | 122.90427(1) u | 0.89(3) % | 9.2 × 1016 a | 1/2+ |
| Isotope 124Te | 123.90282(1) u | 4.74(14) % | stable | 0+ |
| Isotope 125Te | 124.9044312(15) u | 7.07(15) % | stable | 1/2+ |
| Isotope 126Te | 125.90331(1) u | 18.84(25) % | stable | 0+ |
| Isotope 128Te | 127.904461(6) u | 31.74(8) % | 7.7(4) × 1024 a | 0+ |
| Isotope 130Te | 129.90622275(8) u | 34.08(62) % | 0.79 × 1021 a | 0+ |
NMR data
Nuclear magnetic properties of the NMR active Nuclide 123Te
Isotope:123Te-NMRQuantity:0.89(3) %Spin:1/2+Nuclearmagnetic moment
μ/μN:-0.7358(3)Gyromagnetic ratio γ:7.0576 · 107 rad T-1 s-1Nuclear g-factor:gl = -1.4716Resonance frequency:v0 = 11.2349 at 1 TRelative Sensitivity:0.01837 (H0 = const.)
0.2639 (v0 = const.)
[related to 1H = 1.000]
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 |
|---|
| 123mTe | 247.47(4) keV | 119.2(1) d | 11/2- |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 71) and isobaric (same nucleon number A = 123) with Tellurium-123. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 71 | Isobar A = 123 |
|---|
| 40 | 111Zr | |
| 41 | 112Nb | |
| 42 | 113Mo | |
| 43 | 114Tc | |
| 44 | 115Ru | 123Ru |
| 45 | 116Rh | 123Rh |
| 46 | 117Pd | 123Pd |
| 47 | 118Ag | 123Ag |
| 48 | 119Cd | 123Cd |
| 49 | 120In | 123In |
| 50 | 121Sn | 123Sn |
| 51 | 122Sb | 123Sb |
| 52 | 123Te | 123Te |
| 53 | 124I | 123I |
| 54 | 125Xe | 123Xe |
| 55 | 126Cs | 123Cs |
| 56 | 127Ba | 123Ba |
| 57 | 128La | 123La |
| 58 | 129Ce | 123Ce |
| 59 | 130Pr | 123Pr |
| 60 | 131Nd | |
| 61 | 132Pm | |
| 62 | 133Sm | |
| 63 | 134Eu | |
| 64 | 135Gd | |
| 65 | 136Tb | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/tellurium-123
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