Bismuth-207m

Properties and data of the isotope ^207mBi.

Contents

General data

Name of the isotope:Bismuth-207m; Bi-207mSymbol:^207mBi or 207m83BiMass number A:207 (= number of nucleons)Atomic number Z:83 (= number of protons)Neutrons N:124Isotopic mass:206.9784705(26) u (atomic weight of Bismuth-207m)
Excitation energy: 2101.61(16) keVNuclide mass:206.9329436 u (calculated nuclear mass without electrons)Mass excess:-20.0546 MeVMass defect:1.74545674 u (per nucleus)Nuclear binding energy:1625.88248057 MeV (per nucleus)
7.85450474 MeV (average binding energy per nucleon)Half-life:182(6) μsDecay constant λ:3808.5009920876 s^-1Specific activity α:1.113365506774 × 10⁺²⁵ Bq g^-1
3.009095964256 × 10⁺¹⁴ Ci g^-1Spin and parity:
(nuclear angular momentum)21/2+

Radioactive Decay

Half-life T_½ = 182(6) μs respectively 1.82 × 10^-4 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	²⁰⁷Bi	100 %

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
²⁰⁷Bi		31.55(4) a	9/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 124) and isobaric (same nucleon number A = 207) with Bismuth-207m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 124	Isobar A = 207
75	¹⁹⁹Re
76	²⁰⁰Os
77	²⁰¹Ir
78	²⁰²Pt	²⁰⁷Pt
79	²⁰³Au	²⁰⁷Au
80	²⁰⁴Hg	²⁰⁷Hg
81	²⁰⁵Tl	²⁰⁷Tl
82	²⁰⁶Pb	²⁰⁷Pb
83	²⁰⁷Bi	²⁰⁷Bi
84	²⁰⁸Po	²⁰⁷Po
85	²⁰⁹At	²⁰⁷At
86	²¹⁰Rn	²⁰⁷Rn
87	²¹¹Fr	²⁰⁷Fr
88	²¹²Ra	²⁰⁷Ra
89	²¹³Ac	²⁰⁷Ac
90	²¹⁴Th	²⁰⁷Th
91	²¹⁵Pa
92	²¹⁶U