Polonium-216

Properties and data of the isotope ²¹⁶Po.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

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

General data

Name of the isotope:Polonium-216; Po-216Other names:Thorium ASymbol:²¹⁶Po or 21684PoMass number A:216 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:132Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.5714285714286 (= neutron-proton ratio)Neutron excess (N-Z):48Isotopic mass:216.0019135(19) u (atomic weight of Polonium-216)Nuclide mass:215.9558382 u (calculated nuclear mass without electrons)Mass excess:1.78241 MeVMass defect:1.7991581 u (per nucleus)Nuclear binding energy:1675.9049752 MeV (per nucleus)
7.75881933 MeV (average binding energy per nucleon)Separation energy:S_N = 5.7472(23) MeV (first neutron)
S_P = 7.136(6) MeV (first proton)Half-life:0.145(2) sDecay constant λ:4.780325383172 s^-1Specific activity α:1.332768185823 × 10⁺²² Bq g^-1
360207617790.22 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:5.6359(174) femtometer fmYear of discovery:1910

Radioactive Decay

Half-life T_½ = 0.145(2) s respectively 1.45 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²¹²Pb	100 %	6.9063(5) MeV

Parent Nuclides

Direct parent isotopes are: ²²⁰Rn, ²¹⁶Bi.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 132) and isobaric (same nucleon number A = 216) with Polonium-216. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 132	Isobar A = 216
80	²¹²Hg	²¹⁶Hg
81	²¹³Tl	²¹⁶Tl
82	²¹⁴Pb	²¹⁶Pb
83	²¹⁵Bi	²¹⁶Bi
84	²¹⁶Po	²¹⁶Po
85	²¹⁷At	²¹⁶At
86	²¹⁸Rn	²¹⁶Rn
87	²¹⁹Fr	²¹⁶Fr
88	²²⁰Ra	²¹⁶Ra
89	²²¹Ac	²¹⁶Ac
90	²²²Th	²¹⁶Th
91	²²³Pa	²¹⁶Pa
92	²²⁴U	²¹⁶U
93	²²⁵Np

External data and identifiers

CAS:15756-58-8InChI Key:HZEBHPIOVYHPMT-RKEGKUSMSA-NSMILES:[216Po]PubChem:ID 6335815Adopted Levels, Gammas:NuDat 216Po

Literature and References

[1] - J. D. Hey, R. D. Cherry:
The Half-Life of Polonium-216.
In: Transactions of the Royal Society of South Africa, (2010), DOI 10.1080/00359197809520234.