Polonium-206m2

Properties and data of the isotope ²⁰⁶Po.

Content

General data

Name of the isotope:Polonium-206m2; Po-206m2Symbol:²⁰⁶Po or 20684PoMass number A:206 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:122Isotopic mass:205.980474(4) u (atomic weight of Polonium-206m2)
Excitation energy: 2.262.09(12) keVNuclide mass:205.9343987 u (calculated nuclear mass without electrons)Mass excess:-18.18835 MeVMass defect:1.73394844 u (per nucleus)Nuclear binding energy:1615.16256817 MeV (per nucleus)
7.84059499 MeV (average binding energy per nucleon)Half-life:1.05(6) μsDecay constant λ:660140.17196185 s^-1Specific activity α:1.939247367247 × 10⁺²⁷ Bq g^-1
5.241209100668 × 10⁺¹⁶ Ci g^-1Spin and parity:
(nuclear angular momentum)9-

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
²⁰⁶Po		8.8(1) d	0+
^206m1Po	1585.90(11) keV	232(4) ns	8+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 122) and isobaric (same nucleon number A = 206) with Polonium-206m2. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 122	Isobar A = 206
74	¹⁹⁶W
75	¹⁹⁷Re
76	¹⁹⁸Os
77	¹⁹⁹Ir
78	²⁰⁰Pt	²⁰⁶Pt
79	²⁰¹Au	²⁰⁶Au
80	²⁰²Hg	²⁰⁶Hg
81	²⁰³Tl	²⁰⁶Tl
82	²⁰⁴Pb	²⁰⁶Pb
83	²⁰⁵Bi	²⁰⁶Bi
84	²⁰⁶Po	²⁰⁶Po
85	²⁰⁷At	²⁰⁶At
86	²⁰⁸Rn	²⁰⁶Rn
87	²⁰⁹Fr	²⁰⁶Fr
88	²¹⁰Ra	²⁰⁶Ra
89	²¹¹Ac	²⁰⁶Ac
90	²¹²Th
91	²¹³Pa
92	²¹⁴U