Rhodium-123
Properties and data of the isotope 123Rh.
See also: List of individual Rhodium isotopes (and general data sources).
General data
Name of the isotope:Rhodium-123; Rh-123Symbol:123Rh or 12345RhMass number A:123 (= number of nucleons)Atomic number Z:45 (= number of protons)Neutrons N:78Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.7333333333333 (= neutron-proton ratio)Neutron excess (N-Z):33Isotopic mass:122.94701(43) u (atomic weight of Rhodium-123)Nuclide mass:122.9223252 u (calculated nuclear mass without electrons)Mass excess:-49.35987 MeVMass defect:1.080979888 u (per nucleus)Nuclear binding energy:1006.92627979 MeV (per nucleus)
8.18639252 MeV (average binding energy per nucleon)Separation energy:SN = 5.35(50) MeV (first neutron)
SP = 14.50(64) MeV (first proton)Half-life:42(4) msDecay constant λ:16.503504299046 s-1Specific activity α:8.146428489461 × 10+22 Bq g-1
2201737429584.2 Ci g-1Spin and parity:
(nuclear angular momentum)Year of discovery:2010
Radioactive Decay
Half-life T½ = 42(4) ms respectively 4.2 × 10-2 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β- | 123Pd | 100 % | 11.07(88) MeV | |
| β-, n | 122Pd | ? | 7.18(40) MeV | |
| β-, 2n | 121Pd | ? | | |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 78) and isobaric (same nucleon number A = 123) with Rhodium-123. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 78 | Isobar A = 123 |
|---|
| 43 | 121Tc | |
| 44 | 122Ru | 123Ru |
| 45 | 123Rh | 123Rh |
| 46 | 124Pd | 123Pd |
| 47 | 125Ag | 123Ag |
| 48 | 126Cd | 123Cd |
| 49 | 127In | 123In |
| 50 | 128Sn | 123Sn |
| 51 | 129Sb | 123Sb |
| 52 | 130Te | 123Te |
| 53 | 131I | 123I |
| 54 | 132Xe | 123Xe |
| 55 | 133Cs | 123Cs |
| 56 | 134Ba | 123Ba |
| 57 | 135La | 123La |
| 58 | 136Ce | 123Ce |
| 59 | 137Pr | 123Pr |
| 60 | 138Nd | |
| 61 | 139Pm | |
| 62 | 140Sm | |
| 63 | 141Eu | |
| 64 | 142Gd | |
| 65 | 143Tb | |
| 66 | 144Dy | |
| 67 | 145Ho | |
| 68 | 146Er | |
| 69 | 147Tm | |
| 70 | 148Yb | |
| 71 | 149Lu | |
External data and identifiers
Last update: 2020-10-15
Perma link: https://www.chemlin.org/isotope/rhodium-123
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