Bismuth-199m

Properties and data of the isotope ^199mBi.

Contents

General data

Name of the isotope:Bismuth-199m; Bi-199mSymbol:^199mBi or 199m83BiMass number A:199 (= number of nucleons)Atomic number Z:83 (= number of protons)Neutrons N:116Isotopic mass:198.977673(11) u (atomic weight of Bismuth-199m)
Excitation energy: 667(4) keVNuclide mass:198.9321461 u (calculated nuclear mass without electrons)Mass excess:-20.79747 MeVMass defect:1.676934912 u (per nucleus)Nuclear binding energy:1562.05480892 MeV (per nucleus)
7.84952165 MeV (average binding energy per nucleon)Half-life:24.70(15) minDecay constant λ:0.00046771064815111 s^-1Specific activity α:1.422535052958 × 10⁺¹⁸ Bq g^-1
38446893.323208 Ci g^-1Spin and parity:
(nuclear angular momentum)(1/2+)

Radioactive Decay

Half-life T_½ = 24.70(15) min (minutes) respectively 1.482 × 10³ seconds s.

Decay mode	Daughter	Probability
EC/β⁺	¹⁹⁹Pb	99(1) %
α	¹⁹⁵Tl	ca. 0.01 %
Iso	¹⁹⁹Bi	≤ 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
¹⁹⁹Bi		27(1) min	9/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 116) and isobaric (same nucleon number A = 199) with Bismuth-199m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 116	Isobar A = 199
71	¹⁸⁷Lu
72	¹⁸⁸Hf
73	¹⁸⁹Ta
74	¹⁹⁰W
75	¹⁹¹Re	¹⁹⁹Re
76	¹⁹²Os	¹⁹⁹Os
77	¹⁹³Ir	¹⁹⁹Ir
78	¹⁹⁴Pt	¹⁹⁹Pt
79	¹⁹⁵Au	¹⁹⁹Au
80	¹⁹⁶Hg	¹⁹⁹Hg
81	¹⁹⁷Tl	¹⁹⁹Tl
82	¹⁹⁸Pb	¹⁹⁹Pb
83	¹⁹⁹Bi	¹⁹⁹Bi
84	²⁰⁰Po	¹⁹⁹Po
85	²⁰¹At	¹⁹⁹At
86	²⁰²Rn	¹⁹⁹Rn
87	²⁰³Fr	¹⁹⁹Fr
88	²⁰⁴Ra
89	²⁰⁵Ac