Mercury-191m

Properties and data of the isotope ^191mHg.

Contents

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

General data

Name of the isotope:Mercury-191m; Hg-191mSymbol:^191mHg or 191m80HgMass number A:191 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:111Isotopic mass:190.967158(24) u (atomic weight of Mercury-191m)
Excitation energy: +x keVNuclide mass:190.9232764 u (calculated nuclear mass without electrons)Mass excess:-30.59213 MeVMass defect:1.620650236 u (per nucleus)Nuclear binding energy:1509.62597093 MeV (per nucleus)
7.90380089 MeV (average binding energy per nucleon)Half-life:50.8(15) minDecay constant λ:0.00022741049230969 s^-1Specific activity α:7.207884303771 × 10⁺¹⁷ Bq g^-1
19480768.388571 Ci g^-1Spin and parity:
(nuclear angular momentum)13/2(+)Magnetic dipole moment:μ(μ_N) = - 1.068(5)Quadrupole moment Q:0.64(25) barn (100 fm²)Nuclear g-factor:g_l = -0.16430769230769

Radioactive Decay

Half-life T_½ = 50.8(15) min (minutes) respectively 3.048 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁹¹Au	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
¹⁹¹Hg		49(10) min	3/2(-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 111) and isobaric (same nucleon number A = 191) with Mercury-191m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 111	Isobar A = 191
70	¹⁸¹Yb
71	¹⁸²Lu
72	¹⁸³Hf
73	¹⁸⁴Ta	¹⁹¹Ta
74	¹⁸⁵W	¹⁹¹W
75	¹⁸⁶Re	¹⁹¹Re
76	¹⁸⁷Os	¹⁹¹Os
77	¹⁸⁸Ir	¹⁹¹Ir
78	¹⁸⁹Pt	¹⁹¹Pt
79	¹⁹⁰Au	¹⁹¹Au
80	¹⁹¹Hg	¹⁹¹Hg
81	¹⁹²Tl	¹⁹¹Tl
82	¹⁹³Pb	¹⁹¹Pb
83	¹⁹⁴Bi	¹⁹¹Bi
84	¹⁹⁵Po	¹⁹¹Po
85	¹⁹⁶At	¹⁹¹At
86	¹⁹⁷Rn