Polonium-192

Properties and data of the isotope ¹⁹²Po.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Polonium-192; Po-192Symbol:¹⁹²Po or 19284PoMass number A:192 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:108Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.2857142857143 (= neutron-proton ratio)Neutron excess (N-Z):24Isotopic mass:191.991336(12) u (atomic weight of Polonium-192)Nuclide mass:191.9452607 u (calculated nuclear mass without electrons)Mass excess:-8.07046 MeVMass defect:1.601777616 u (per nucleus)Nuclear binding energy:1492.04623864 MeV (per nucleus)
7.77107416 MeV (average binding energy per nucleon)Separation energy:S_N = 11.073(13) MeV (first neutron)
S_P = 2.120(13) MeV (first proton)Half-life:32.2(3) msDecay constant λ:21.526309955278 s^-1Specific activity α:6.787145065201 × 10⁺²² Bq g^-1
1834363531135.4 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:5.5220(178) femtometer fmYear of discovery:1977

Radioactive Decay

Half-life T_½ = 32.2(3) ms respectively 3.22 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁸⁸Pb	ca. 99.5 %	7.230(3) MeV
EC/β⁺	¹⁹²Bi	ca. 0.5 %	5.46(3) MeV

Parent Nuclides

Direct parent isotope is: ¹⁹⁶Rn.

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
^192mPo	2294.6 keV	0.58(10) μs	(11-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 108) and isobaric (same nucleon number A = 192) with Polonium-192. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 108	Isobar A = 192
66	¹⁷⁴Dy
67	¹⁷⁵Ho
68	¹⁷⁶Er
69	¹⁷⁷Tm
70	¹⁷⁸Yb
71	¹⁷⁹Lu
72	¹⁸⁰Hf
73	¹⁸¹Ta	¹⁹²Ta
74	¹⁸²W	¹⁹²W
75	¹⁸³Re	¹⁹²Re
76	¹⁸⁴Os	¹⁹²Os
77	¹⁸⁵Ir	¹⁹²Ir
78	¹⁸⁶Pt	¹⁹²Pt
79	¹⁸⁷Au	¹⁹²Au
80	¹⁸⁸Hg	¹⁹²Hg
81	¹⁸⁹Tl	¹⁹²Tl
82	¹⁹⁰Pb	¹⁹²Pb
83	¹⁹¹Bi	¹⁹²Bi
84	¹⁹²Po	¹⁹²Po
85	¹⁹³At	¹⁹²At
86	¹⁹⁴Rn