Cesium-119
Properties and data of the isotope 119Cs.
See also: List of individual Cesium isotopes (and general data sources).
General data
Name of the isotope:Cesium-119; Cs-119Symbol:119Cs or 11955CsMass number A:119 (= number of nucleons)Atomic number Z:55 (= number of protons)Neutrons N:64Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.1636363636364 (= neutron-proton ratio)Neutron excess (N-Z):9Isotopic mass:118.922377(15) u (atomic weight of Cesium-119)Nuclide mass:118.8922071 u (calculated nuclear mass without electrons)Mass excess:-72.30536 MeVMass defect:1.062554384 u (per nucleus)Nuclear binding energy:989.76303337 MeV (per nucleus)
8.31733641 MeV (average binding energy per nucleon)Separation energy:SN = 11.967(19) MeV (first neutron)
SP = 1.515(17) MeV (first proton)Half-life:43.0(2) sDecay constant λ:0.016119701873487 s-1Specific activity α:8.226704686637 × 10+19 Bq g-1
2223433699.0913 Ci g-1Spin and parity:
(nuclear angular momentum)9/2+Magnetic dipole moment:μ(μN) = + 5.45(3)Quadrupole moment Q:+ 2.80(1) barn (100 fm2)Nuclear g-factor:gl = 1.2111111111111Charge radius:4.7896(89) femtometer fmYear of discovery:1969
Radioactive Decay
Half-life T½ = 43.0(2) s respectively 4.30 × 101 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 119Xe | 100 % | 6.489(17) MeV | |
Parent Nuclides
Direct parent isotope is: 119Ba.
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 |
|---|
| 119mCs | 50 keV | 30.4(1) s | 3/2(+) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 64) and isobaric (same nucleon number A = 119) with Cesium-119. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 64 | Isobar A = 119 |
|---|
| 36 | 100Kr | |
| 37 | 101Rb | |
| 38 | 102Sr | |
| 39 | 103Y | |
| 40 | 104Zr | |
| 41 | 105Nb | |
| 42 | 106Mo | |
| 43 | 107Tc | 119Tc |
| 44 | 108Ru | 119Ru |
| 45 | 109Rh | 119Rh |
| 46 | 110Pd | 119Pd |
| 47 | 111Ag | 119Ag |
| 48 | 112Cd | 119Cd |
| 49 | 113In | 119In |
| 50 | 114Sn | 119Sn |
| 51 | 115Sb | 119Sb |
| 52 | 116Te | 119Te |
| 53 | 117I | 119I |
| 54 | 118Xe | 119Xe |
| 55 | 119Cs | 119Cs |
| 56 | 120Ba | 119Ba |
| 57 | 121La | 119La |
| 58 | 122Ce | 119Ce |
| 59 | 123Pr | |
| 60 | 124Nd | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/cesium-119
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