Mercury-187m

Properties and data of the isotope ^187mHg.

Contents

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

General data

Name of the isotope:Mercury-187m; Hg-187mSymbol:^187mHg or 187m80HgMass number A:187 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:107Isotopic mass:186.969814(15) u (atomic weight of Mercury-187m)Nuclide mass:186.9259324 u (calculated nuclear mass without electrons)Mass excess:-28.11808 MeVMass defect:1.583334572 u (per nucleus)Nuclear binding energy:1474.86665381 MeV (per nucleus)
7.88698745 MeV (average binding energy per nucleon)Half-life:2.4(3) minDecay constant λ:0.0048135220872218 s^-1Specific activity α:1.558478926971 × 10⁺¹⁹ Bq g^-1
421210520.80305 Ci g^-1Spin and parity:
(nuclear angular momentum)13/2(+)Magnetic dipole moment:μ(μ_N) = - 1.044(11)Quadrupole moment Q:+ 0.50(30) barn (100 fm²)Nuclear g-factor:g_l = -0.16061538461538

Radioactive Decay

Half-life T_½ = 2.4(3) min (minutes) respectively 1.44 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁸³Pt	trace
EC/β⁺	¹⁸⁷Au	>> 99 %

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
¹⁸⁷Hg		1.9(3) min	3/2(-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 107) and isobaric (same nucleon number A = 187) with Mercury-187m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 107	Isobar A = 187
65	¹⁷²Tb
66	¹⁷³Dy
67	¹⁷⁴Ho
68	¹⁷⁵Er
69	¹⁷⁶Tm
70	¹⁷⁷Yb
71	¹⁷⁸Lu	¹⁸⁷Lu
72	¹⁷⁹Hf	¹⁸⁷Hf
73	¹⁸⁰Ta	¹⁸⁷Ta
74	¹⁸¹W	¹⁸⁷W
75	¹⁸²Re	¹⁸⁷Re
76	¹⁸³Os	¹⁸⁷Os
77	¹⁸⁴Ir	¹⁸⁷Ir
78	¹⁸⁵Pt	¹⁸⁷Pt
79	¹⁸⁶Au	¹⁸⁷Au
80	¹⁸⁷Hg	¹⁸⁷Hg
81	¹⁸⁸Tl	¹⁸⁷Tl
82	¹⁸⁹Pb	¹⁸⁷Pb
83	¹⁹⁰Bi	¹⁸⁷Bi
84	¹⁹¹Po	¹⁸⁷Po
85	¹⁹²At
86	¹⁹³Rn