Bismuth-212m2

Properties and data of the isotope ^212m2Bi.

Contents

General data

Name of the isotope:Bismuth-212m2; Bi-212m2Symbol:^212m2Bi or 212m283BiMass 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-212m2)
Excitation energy: 1910 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:7.0(3) minDecay constant λ:0.0016503504299046 s^-1Specific activity α:4.710257230873 × 10⁺¹⁸ Bq g^-1
127304249.48306 Ci g^-1Spin and parity:
(nuclear angular momentum)

Radioactive Decay

Half-life T_½ = 7.0(3) min (minutes) respectively 4.20 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²¹²Po	ca. 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
²¹²Bi		60.55(6) min	1(-)
^212m1Bi	250 keV	25.0(2) min	(8-,9-)

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-212m2. 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