Polonium-211m3

Properties and data of the isotope ^211m3Po.

Contents

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

General data

Name of the isotope:Polonium-211m3; Po-211m3Symbol:^211m3Po or 211m384PoMass number A:211 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:127Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.5119047619048 (= neutron-proton ratio)Neutron excess (N-Z):43Excitation energy:4872(6) keVIsotopic mass:210.9866531(13) u (atomic weight of Polonium-211m3)Nuclide mass:210.9405778 u (calculated nuclear mass without electrons)Mass excess:-12.43256 MeVMass defect:1.77109392 u (per nucleus)Nuclear binding energy:1649.76335992 MeV (per nucleus)
7.8187837 MeV (average binding energy per nucleon)Half-life:2.8(7) μsDecay constant λ:247552.56448569 s^-1Specific activity α:7.099030540816 × 10⁺²⁶ Bq g^-1
1.918656902923 × 10⁺¹⁶ Ci g^-1Spin and parity:
(nuclear angular momentum)(43/2+)

Radioactive Decay

Half-life T_½ = 2.8(7) μs respectively 2.8 × 10^-6 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	²¹¹Po	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
^211m1Po	1462(5) keV	25.2(6) s	(25/2+)
^211m2Po	2135(5) keV	243(21) ns	(31/2-)
²¹¹Po		0.516(3) s	9/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 127) and isobaric (same nucleon number A = 211) with Polonium-211m3. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 127	Isobar A = 211
76	²⁰³Os
77	²⁰⁴Ir
78	²⁰⁵Pt
79	²⁰⁶Au
80	²⁰⁷Hg	²¹¹Hg
81	²⁰⁸Tl	²¹¹Tl
82	²⁰⁹Pb	²¹¹Pb
83	²¹⁰Bi	²¹¹Bi
84	²¹¹Po	²¹¹Po
85	²¹²At	²¹¹At
86	²¹³Rn	²¹¹Rn
87	²¹⁴Fr	²¹¹Fr
88	²¹⁵Ra	²¹¹Ra
89	²¹⁶Ac	²¹¹Ac
90	²¹⁷Th	²¹¹Th
91	²¹⁸Pa
92	²¹⁹U
93	²²⁰Np