Polonium-223

Properties and data of the isotope ²²³Po.

Contents

See also: List of individual Polonium isotopes (and general data sources).

General data

Name of the isotope:Polonium-223; Po-223Symbol:²²³Po or 22384PoMass number A:223 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:139Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.6547619047619 (= neutron-proton ratio)Neutron excess (N-Z):55Isotopic mass:223.02907(21) u (atomic weight of Polonium-223)Nuclide mass:222.9829947 u (calculated nuclear mass without electrons)Mass excess:27.07853 MeVMass defect:1.832656012 u (per nucleus)Nuclear binding energy:1707.10807924 MeV (per nucleus)
7.65519318 MeV (average binding energy per nucleon)Separation energy:S_N = 3.48(20) MeV (first neutron)
S_P = 8.94(36) MeV (first proton)Half-life:300 nsDecay constant λ:2310490.6018665 s^-1Specific activity α:6.239506663677 × 10⁺²⁷ Bq g^-1
1.686353152345 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:2010

Radioactive Decay

Half-life T_½ = 300 ns respectively 3.0 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²²³At	?	3.65(20) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 139) and isobaric (same nucleon number A = 223) with Polonium-223. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 139	Isobar A = 223
83	²²²Bi	²²³Bi
84	²²³Po	²²³Po
85	²²⁴At	²²³At
86	²²⁵Rn	²²³Rn
87	²²⁶Fr	²²³Fr
88	²²⁷Ra	²²³Ra
89	²²⁸Ac	²²³Ac
90	²²⁹Th	²²³Th
91	²³⁰Pa	²²³Pa
92	²³¹U	²²³U
93	²³²Np	²²³Np
94	²³³Pu
95	²³⁴Am	²²³Am
96	²³⁵Cm
97	²³⁶Bk
98	²³⁷Cf