Polonium-198m1

Properties and data of the isotope ^198m1Po.

Contents

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

General data

Name of the isotope:Polonium-198m1; Po-198m1Symbol:^198m1Po or 198m184PoMass number A:198 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:114Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3571428571429 (= neutron-proton ratio)Neutron excess (N-Z):30Excitation energy:2565.92(20) keVIsotopic mass:197.983389(19) u (atomic weight of Polonium-198m1)Nuclide mass:197.9373137 u (calculated nuclear mass without electrons)Mass excess:-15.47305 MeVMass defect:1.661714112 u (per nucleus)Nuclear binding energy:1547.87672504 MeV (per nucleus)
7.81755922 MeV (average binding energy per nucleon)Half-life:200(20) nsDecay constant λ:3465735.9027997 s^-1Specific activity α:1.059449227918 × 10⁺²⁸ Bq g^-1
2.863376291672 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)11-

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
¹⁹⁸Po		1.760(24) min	0+
^198m2Po	2691.86+x keV	0.75(5) μs	12+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 114) and isobaric (same nucleon number A = 198) with Polonium-198m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 114	Isobar A = 198
70	¹⁸⁴Yb
71	¹⁸⁵Lu
72	¹⁸⁶Hf
73	¹⁸⁷Ta
74	¹⁸⁸W
75	¹⁸⁹Re	¹⁹⁸Re
76	¹⁹⁰Os	¹⁹⁸Os
77	¹⁹¹Ir	¹⁹⁸Ir
78	¹⁹²Pt	¹⁹⁸Pt
79	¹⁹³Au	¹⁹⁸Au
80	¹⁹⁴Hg	¹⁹⁸Hg
81	¹⁹⁵Tl	¹⁹⁸Tl
82	¹⁹⁶Pb	¹⁹⁸Pb
83	¹⁹⁷Bi	¹⁹⁸Bi
84	¹⁹⁸Po	¹⁹⁸Po
85	¹⁹⁹At	¹⁹⁸At
86	²⁰⁰Rn	¹⁹⁸Rn
87	²⁰¹Fr
88	²⁰²Ra
89	²⁰³Ac