See also: List of individual Francium isotopes (and general data sources).
General data
Name of the isotope:Francium-223; Fr-223Other names:Actinium KSymbol:223Fr or 22387FrMass number A:223 (= number of nucleons)Atomic number Z:87 (= number of protons)Neutrons N:136Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.5632183908046 (= neutron-proton ratio)Neutron excess (N-Z):49Isotopic mass:223.0197343(21) u (atomic weight of Francium-223)Nuclide mass:222.9720137 u (calculated nuclear mass without electrons)Mass excess:18.38238 MeVMass defect:1.83947206 u (per nucleus)Nuclear binding energy:1713.45718706 MeV (per nucleus) 7.68366452 MeV (average binding energy per nucleon)Separation energy:SN = 6.067(8) MeV (first neutron) SP = 5.2788(23) MeV (first proton)Half-life:22.00(7) minDecay constant λ:0.0005251115004242 s-1Specific activity α:1.417944192326 × 10+18 Bq g-1 38322816.00883 Ci g-1Spin and parity: (nuclear angular momentum)3/2(-)Magnetic dipole moment:μ(μN) = + 1.17(2)Charge radius:5.6951(178) femtometer fmYear of discovery:1939
Radioactive Decay
Half-life T½ = 22.00(7) min (minutes) respectively 1.320 × 103 seconds s.
Comparison of the natural Francium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
Atomic Mass ma
Quantity
Half-life
Spin
Francium Isotopic mixture
223.019736138 u
100 %
Isotope 223Fr
223.0197343(21) u
100 %
22.00(7) min
3/2(-)
NMR data
Nuclear magnetic properties and parameters of the NMR active Nuclide223Fr
Isotope:223Fr-NMRQuantity:100 %Spin:3/2(-)Nuclearmagnetic moment μ/μN:+ 1.17(2)Nuclear g-factor:gl = 0.78Quadrupole moment Q:1.18(2) barn (100 fm2)Line width parameter (factor):l = 18565.33 fm4Resonance frequency:v0 = 5.94 MHz at 1 TRelative Sensitivity:[related to 1H = 1.000]: 0.01362 (H0 = const.) 0.6982 (v0 = const.)
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 136) and isobaric (same nucleon number A = 223) with Francium-223. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
