Gold-198m1

Properties and data of the isotope ¹⁹⁸Au.

Content

General data

Name of the isotope:Gold-198m1; Gold-198m1Symbol:¹⁹⁸Au or 19879AuMass number A:198 (= number of nucleons)Atomic number Z:79 (= number of protons)Neutrons N:119Isotopic mass:197.9682437(6) u (atomic weight of Gold-198m1)
Excitation energy: 312.2227(20) keVNuclide mass:197.9249106 u (calculated nuclear mass without electrons)Mass excess:-29.5808 MeVMass defect:1.681058832 u (per nucleus)Nuclear binding energy:1565.89621566 MeV (per nucleus)
7.90856675 MeV (average binding energy per nucleon)Half-life:124(4) nsDecay constant λ:5589896.6174189 s^-1Specific activity α:1.708789077288 × 10⁺²⁸ Bq g^-1
4.618348857536 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)5+Magnetic dipole moment:μ(μ_N) = -1.11(2)Nuclear g-factor:g_l = -0.222

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
¹⁹⁸Au		2.6941(2) d	2-
^198m2Au	811.7(15) keV	2.272(16) d	(12-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 119) and isobaric (same nucleon number A = 198) with Gold-198m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 119	Isobar A = 198
73	¹⁹²Ta
74	¹⁹³W
75	¹⁹⁴Re	¹⁹⁸Re
76	¹⁹⁵Os	¹⁹⁸Os
77	¹⁹⁶Ir	¹⁹⁸Ir
78	¹⁹⁷Pt	¹⁹⁸Pt
79	¹⁹⁸Au	¹⁹⁸Au
80	¹⁹⁹Hg	¹⁹⁸Hg
81	²⁰⁰Tl	¹⁹⁸Tl
82	²⁰¹Pb	¹⁹⁸Pb
83	²⁰²Bi	¹⁹⁸Bi
84	²⁰³Po	¹⁹⁸Po
85	²⁰⁴At	¹⁹⁸At
86	²⁰⁵Rn	¹⁹⁸Rn
87	²⁰⁶Fr
88	²⁰⁷Ra
89	²⁰⁸Ac
90	²⁰⁹Th