Lead-216

Properties and data of the isotope ²¹⁶Pb.

Contents

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

General data

Name of the isotope:Lead-216; Pb-216Symbol:²¹⁶Pb or 21682PbMass number A:216 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:134Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.6341463414634 (= neutron-proton ratio)Neutron excess (N-Z):52Isotopic mass:216.00803(21) u (atomic weight of Lead-216)Nuclide mass:215.9630516 u (calculated nuclear mass without electrons)Mass excess:7.4799 MeVMass defect:1.794721368 u (per nucleus)Nuclear binding energy:1671.77218596 MeV (per nucleus)
7.73968605 MeV (average binding energy per nucleon)Separation energy:S_N = 4.93(20) MeV (first neutron)
S_P = 9.72(36) MeV (first proton)Half-life:300 nsDecay constant λ:2310490.6018665 s^-1Specific activity α:6.441712898148 × 10⁺²⁷ Bq g^-1
1.74100348598 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:2009

Radioactive Decay

Half-life T_½ = 300 ns respectively 3.0 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²¹⁶Bi	?	1.61(20) MeV

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
^216mPb	1459+x keV	0.40(4) μs	(8+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 134) and isobaric (same nucleon number A = 216) with Lead-216. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 134	Isobar A = 216
80	²¹⁴Hg	²¹⁶Hg
81	²¹⁵Tl	²¹⁶Tl
82	²¹⁶Pb	²¹⁶Pb
83	²¹⁷Bi	²¹⁶Bi
84	²¹⁸Po	²¹⁶Po
85	²¹⁹At	²¹⁶At
86	²²⁰Rn	²¹⁶Rn
87	²²¹Fr	²¹⁶Fr
88	²²²Ra	²¹⁶Ra
89	²²³Ac	²¹⁶Ac
90	²²⁴Th	²¹⁶Th
91	²²⁵Pa	²¹⁶Pa
92	²²⁶U	²¹⁶U
93	²²⁷Np
94	²²⁸Pu
95	²²⁹Am