Bismuth-197m

Properties and data of the isotope ^197mBi.

Contents

General data

Name of the isotope:Bismuth-197m; Bi-197mSymbol:^197mBi or 197m83BiMass number A:197 (= number of nucleons)Atomic number Z:83 (= number of protons)Neutrons N:114Isotopic mass:196.978865(9) u (atomic weight of Bismuth-197m)
Excitation energy: 500 keVNuclide mass:196.9333381 u (calculated nuclear mass without electrons)Mass excess:-19.68713 MeVMass defect:1.65841308 u (per nucleus)Nuclear binding energy:1544.80183354 MeV (per nucleus)
7.84163367 MeV (average binding energy per nucleon)Half-life:5.04(16) minDecay constant λ:0.0022921533748675 s^-1Specific activity α:7.042689028587 × 10⁺¹⁸ Bq g^-1
190342946.71858 Ci g^-1Spin and parity:
(nuclear angular momentum)(1/2+)

Radioactive Decay

Half-life T_½ = 5.04(16) min (minutes) respectively 3.024 × 10² seconds s.

Decay mode	Daughter	Probability
α	¹⁹³Tl	55(40) %
EC/β⁺	¹⁹⁷Pb	45(40) %
Iso	¹⁹⁷Bi	< 0.3 %

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
¹⁹⁷Bi		9.33(50) min	(9/2-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 114) and isobaric (same nucleon number A = 197) with Bismuth-197m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 114	Isobar A = 197
70	¹⁸⁴Yb
71	¹⁸⁵Lu
72	¹⁸⁶Hf
73	¹⁸⁷Ta
74	¹⁸⁸W	¹⁹⁷W
75	¹⁸⁹Re	¹⁹⁷Re
76	¹⁹⁰Os	¹⁹⁷Os
77	¹⁹¹Ir	¹⁹⁷Ir
78	¹⁹²Pt	¹⁹⁷Pt
79	¹⁹³Au	¹⁹⁷Au
80	¹⁹⁴Hg	¹⁹⁷Hg
81	¹⁹⁵Tl	¹⁹⁷Tl
82	¹⁹⁶Pb	¹⁹⁷Pb
83	¹⁹⁷Bi	¹⁹⁷Bi
84	¹⁹⁸Po	¹⁹⁷Po
85	¹⁹⁹At	¹⁹⁷At
86	²⁰⁰Rn	¹⁹⁷Rn
87	²⁰¹Fr
88	²⁰²Ra
89	²⁰³Ac