Lead-188m2

Properties and data of the isotope ^188m2Pb.

Contents

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

General data

Name of the isotope:Lead-188m2; Pb-188m2Symbol:^188m2Pb or 188m282PbMass number A:188 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:106Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.2926829268293 (= neutron-proton ratio)Neutron excess (N-Z):24Excitation energy:4783.4(7) keVIsotopic mass:187.980875(11) u (atomic weight of Lead-188m2)Nuclide mass:187.9358966 u (calculated nuclear mass without electrons)Mass excess:-17.81482 MeVMass defect:1.57925872 u (per nucleus)Nuclear binding energy:1471.07002213 MeV (per nucleus)
7.82484054 MeV (average binding energy per nucleon)Half-life:0.44(6) μsDecay constant λ:1575334.5012726 s^-1Specific activity α:5.073201212931 × 10⁺²⁷ Bq g^-1
1.371135462954 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)(19-)

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
¹⁸⁸Pb		25.5(1) s	0+
^188m1Pb	2577.2(4) keV	800(20) ns	(8-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 106) and isobaric (same nucleon number A = 188) with Lead-188m2. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 106	Isobar A = 188
64	¹⁷⁰Gd
65	¹⁷¹Tb
66	¹⁷²Dy
67	¹⁷³Ho
68	¹⁷⁴Er
69	¹⁷⁵Tm
70	¹⁷⁶Yb
71	¹⁷⁷Lu	¹⁸⁸Lu
72	¹⁷⁸Hf	¹⁸⁸Hf
73	¹⁷⁹Ta	¹⁸⁸Ta
74	¹⁸⁰W	¹⁸⁸W
75	¹⁸¹Re	¹⁸⁸Re
76	¹⁸²Os	¹⁸⁸Os
77	¹⁸³Ir	¹⁸⁸Ir
78	¹⁸⁴Pt	¹⁸⁸Pt
79	¹⁸⁵Au	¹⁸⁸Au
80	¹⁸⁶Hg	¹⁸⁸Hg
81	¹⁸⁷Tl	¹⁸⁸Tl
82	¹⁸⁸Pb	¹⁸⁸Pb
83	¹⁸⁹Bi	¹⁸⁸Bi
84	¹⁹⁰Po	¹⁸⁸Po
85	¹⁹¹At	¹⁸⁸At