Bismuth-212m1

Properties and data of the isotope ^212m1Bi.

Contents

General data

Name of the isotope:Bismuth-212m1; Bi-212m1Symbol:^212m1Bi or 212m183BiMass number A:212 (= number of nucleons)Atomic number Z:83 (= number of protons)Neutrons N:129Isotopic mass:211.991285(2) u (atomic weight of Bismuth-212m1)
Excitation energy: 250 keVNuclide mass:211.9457581 u (calculated nuclear mass without electrons)Mass excess:-8.11797 MeVMass defect:1.77596682 u (per nucleus)Nuclear binding energy:1654.30243703 MeV (per nucleus)
7.80331338 MeV (average binding energy per nucleon)Half-life:25.0(2) minDecay constant λ:0.0004620981203733 s^-1Specific activity α:1.318872024644 × 10⁺¹⁸ Bq g^-1
35645189.855257 Ci g^-1Spin and parity:
(nuclear angular momentum)(8-.9-)

Radioactive Decay

Half-life T_½ = 25.0(2) min (minutes) respectively 1.500 × 10³ seconds s.

Decay mode	Daughter	Probability
β^-	²¹²Po	33(1) %
α	²⁰⁸Tl	67(1) %
β^-, α	²⁰⁸Pb	30(1) %

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
²¹²Bi		60.55(6) min	1(-)
^212m2Bi	1910 keV	7.0(3) min

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 129) and isobaric (same nucleon number A = 212) with Bismuth-212m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 129	Isobar A = 212
78	²⁰⁷Pt
79	²⁰⁸Au
80	²⁰⁹Hg	²¹²Hg
81	²¹⁰Tl	²¹²Tl
82	²¹¹Pb	²¹²Pb
83	²¹²Bi	²¹²Bi
84	²¹³Po	²¹²Po
85	²¹⁴At	²¹²At
86	²¹⁵Rn	²¹²Rn
87	²¹⁶Fr	²¹²Fr
88	²¹⁷Ra	²¹²Ra
89	²¹⁸Ac	²¹²Ac
90	²¹⁹Th	²¹²Th
91	²²⁰Pa	²¹²Pa
92	²²¹U