Mercury-199m

Properties and data of the isotope ^199mHg.

Contents

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

General data

Name of the isotope:Mercury-199m; Hg-199mSymbol:^199mHg or 199m80HgMass number A:199 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:119Isotopic mass:198.968281(3) u (atomic weight of Mercury-199m)
Excitation energy: 532.48(19) keVNuclide mass:198.9243994 u (calculated nuclear mass without electrons)Mass excess:-29.54606 MeVMass defect:1.688846564 u (per nucleus)Nuclear binding energy:1573.15044129 MeV (per nucleus)
7.9052786 MeV (average binding energy per nucleon)Half-life:42.67(9) minDecay constant λ:0.00027073946588546 s^-1Specific activity α:8.234501009627 × 10⁺¹⁷ Bq g^-1
22255408.134129 Ci g^-1Spin and parity:
(nuclear angular momentum)13/2+Magnetic dipole moment:μ(μ_N) = - 1.014703(3)Quadrupole moment Q:+ 1.20(5) barn (100 fm²)Nuclear g-factor:g_l = -0.15610815384615

Radioactive Decay

Half-life T_½ = 42.67(9) min (minutes) respectively 2.5602 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁹⁹Hg	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
¹⁹⁹Hg		stable	1/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 119) and isobaric (same nucleon number A = 199) with Mercury-199m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 119	Isobar A = 199
73	¹⁹²Ta
74	¹⁹³W
75	¹⁹⁴Re	¹⁹⁹Re
76	¹⁹⁵Os	¹⁹⁹Os
77	¹⁹⁶Ir	¹⁹⁹Ir
78	¹⁹⁷Pt	¹⁹⁹Pt
79	¹⁹⁸Au	¹⁹⁹Au
80	¹⁹⁹Hg	¹⁹⁹Hg
81	²⁰⁰Tl	¹⁹⁹Tl
82	²⁰¹Pb	¹⁹⁹Pb
83	²⁰²Bi	¹⁹⁹Bi
84	²⁰³Po	¹⁹⁹Po
85	²⁰⁴At	¹⁹⁹At
86	²⁰⁵Rn	¹⁹⁹Rn
87	²⁰⁶Fr	¹⁹⁹Fr
88	²⁰⁷Ra
89	²⁰⁸Ac
90	²⁰⁹Th
91	²¹⁰Pa