Polonium-207m1

Properties and data of the isotope ^207m1Po.

Contents

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

General data

Name of the isotope:Polonium-207m1; Po-207m1Symbol:^207m1Po or 207m184PoMass number A:207 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:123Isotopic mass:206.981593(7) u (atomic weight of Polonium-207m1)
Excitation energy: 68.557(14) keVNuclide mass:206.9355177 u (calculated nuclear mass without electrons)Mass excess:-17.14601 MeVMass defect:1.741494356 u (per nucleus)Nuclear binding energy:1622.19154365 MeV (per nucleus)
7.83667412 MeV (average binding energy per nucleon)Half-life:205(10) nsDecay constant λ:3381205.758829 s^-1Specific activity α:9.88451327965 × 10⁺²⁷ Bq g^-1
2.671490075583 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-

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
²⁰⁷Po		5.80(2) h	5/2-
^207m2Po	1115.076(17) keV	49(4) μs	13/2+
^207m3Po		2.79(8) s	19/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 123) and isobaric (same nucleon number A = 207) with Polonium-207m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 123	Isobar A = 207
74	¹⁹⁷W
75	¹⁹⁸Re
76	¹⁹⁹Os
77	²⁰⁰Ir
78	²⁰¹Pt	²⁰⁷Pt
79	²⁰²Au	²⁰⁷Au
80	²⁰³Hg	²⁰⁷Hg
81	²⁰⁴Tl	²⁰⁷Tl
82	²⁰⁵Pb	²⁰⁷Pb
83	²⁰⁶Bi	²⁰⁷Bi
84	²⁰⁷Po	²⁰⁷Po
85	²⁰⁸At	²⁰⁷At
86	²⁰⁹Rn	²⁰⁷Rn
87	²¹⁰Fr	²⁰⁷Fr
88	²¹¹Ra	²⁰⁷Ra
89	²¹²Ac	²⁰⁷Ac
90	²¹³Th	²⁰⁷Th
91	²¹⁴Pa
92	²¹⁵U