Mercury-197m

Properties and data of the isotope ^197mHg.

Contents

See also: List of individual Mercury isotopes (and general data sources).

General data

Name of the isotope:Mercury-197m; Hg-197mSymbol:^197mHg or 197m80HgMass number A:197 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:117Isotopic mass:196.967214(3) u (atomic weight of Mercury-197m)
Excitation energy: 298.93(8) keVNuclide mass:196.9233324 u (calculated nuclear mass without electrons)Mass excess:-30.53996 MeVMass defect:1.672583732 u (per nucleus)Nuclear binding energy:1558.00171086 MeV (per nucleus)
7.90863813 MeV (average binding energy per nucleon)Half-life:23.8(1) hDecay constant λ:8.089953087767 × 10^-6 s^-1Specific activity α:2.485654951266 × 10⁺¹⁶ Bq g^-1
671798.63547735 Ci g^-1Spin and parity:
(nuclear angular momentum)13/2+

Radioactive Decay

Half-life T_½ = 23.8(1) h (hours) respectively 8.5680 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁹⁷Au	8.6(7) %
Iso	¹⁹⁷Hg	91.4(7) %

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
¹⁹⁷Hg		64.14(5) h	1/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 117) and isobaric (same nucleon number A = 197) with Mercury-197m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 117	Isobar A = 197
71	¹⁸⁸Lu
72	¹⁸⁹Hf
73	¹⁹⁰Ta
74	¹⁹¹W	¹⁹⁷W
75	¹⁹²Re	¹⁹⁷Re
76	¹⁹³Os	¹⁹⁷Os
77	¹⁹⁴Ir	¹⁹⁷Ir
78	¹⁹⁵Pt	¹⁹⁷Pt
79	¹⁹⁶Au	¹⁹⁷Au
80	¹⁹⁷Hg	¹⁹⁷Hg
81	¹⁹⁸Tl	¹⁹⁷Tl
82	¹⁹⁹Pb	¹⁹⁷Pb
83	²⁰⁰Bi	¹⁹⁷Bi
84	²⁰¹Po	¹⁹⁷Po
85	²⁰²At	¹⁹⁷At
86	²⁰³Rn	¹⁹⁷Rn
87	²⁰⁴Fr
88	²⁰⁵Ra
89	²⁰⁶Ac
90	²⁰⁷Th