Lead-214m

Properties and data of the isotope ^214mPb.

Contents

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

General data

Name of the isotope:Lead-214m; Pb-214mSymbol:^214mPb or 214m82PbMass number A:214 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:132Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.609756097561 (= neutron-proton ratio)Neutron excess (N-Z):50Excitation energy:1365+x keVIsotopic mass:213.9998038(21) u (atomic weight of Lead-214m)Nuclide mass:213.9548254 u (calculated nuclear mass without electrons)Mass excess:-0.18276 MeVMass defect:1.785617736 u (per nucleus)Nuclear binding energy:1663.29220738 MeV (per nucleus)
7.77239349 MeV (average binding energy per nucleon)Half-life:6.2(3) μsDecay constant λ:111797.93234838 s^-1Specific activity α:3.160858668786 × 10⁺²⁶ Bq g^-1
8.542861266991 × 10⁺¹⁵ Ci g^-1Spin and parity:
(nuclear angular momentum)(8+)

Radioactive Decay

Half-life T_½ = 6.2(3) μs respectively 6.2 × 10^-6 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	²¹⁴Pb

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
²¹⁴Pb		27.06(7) min	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 132) and isobaric (same nucleon number A = 214) with Lead-214m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 132	Isobar A = 214
80	²¹²Hg	²¹⁴Hg
81	²¹³Tl	²¹⁴Tl
82	²¹⁴Pb	²¹⁴Pb
83	²¹⁵Bi	²¹⁴Bi
84	²¹⁶Po	²¹⁴Po
85	²¹⁷At	²¹⁴At
86	²¹⁸Rn	²¹⁴Rn
87	²¹⁹Fr	²¹⁴Fr
88	²²⁰Ra	²¹⁴Ra
89	²²¹Ac	²¹⁴Ac
90	²²²Th	²¹⁴Th
91	²²³Pa	²¹⁴Pa
92	²²⁴U	²¹⁴U
93	²²⁵Np