Osmium-197

Properties and data of the isotope ¹⁹⁷Os.

Contents

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

General data

Name of the isotope:Osmium-197; Os-197Symbol:¹⁹⁷Os or 19776OsMass number A:197 (= number of nucleons)Atomic number Z:76 (= number of protons)Neutrons N:121Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.5921052631579 (= neutron-proton ratio)Neutron excess (N-Z):45Isotopic mass:196.97283(21) u (atomic weight of Osmium-197)Nuclide mass:196.9311422 u (calculated nuclear mass without electrons)Mass excess:-25.30869 MeVMass defect:1.670327268 u (per nucleus)Nuclear binding energy:1555.89982818 MeV (per nucleus)
7.89796867 MeV (average binding energy per nucleon)Separation energy:S_N = 5.10(20) MeV (first neutron)
S_P = 10.06(36) MeV (first proton)Half-life:2.8(6) minDecay constant λ:0.0041258760747616 s^-1Specific activity α:1.267684025145 × 10⁺¹⁹ Bq g^-1
342617304.09346 Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:2003

Radioactive Decay

Half-life T_½ = 2.8(6) min (minutes) respectively 1.68 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁹⁷Ir	100 %	2.95(20) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 121) and isobaric (same nucleon number A = 197) with Osmium-197. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 121	Isobar A = 197
73	¹⁹⁴Ta
74	¹⁹⁵W	¹⁹⁷W
75	¹⁹⁶Re	¹⁹⁷Re
76	¹⁹⁷Os	¹⁹⁷Os
77	¹⁹⁸Ir	¹⁹⁷Ir
78	¹⁹⁹Pt	¹⁹⁷Pt
79	²⁰⁰Au	¹⁹⁷Au
80	²⁰¹Hg	¹⁹⁷Hg
81	²⁰²Tl	¹⁹⁷Tl
82	²⁰³Pb	¹⁹⁷Pb
83	²⁰⁴Bi	¹⁹⁷Bi
84	²⁰⁵Po	¹⁹⁷Po
85	²⁰⁶At	¹⁹⁷At
86	²⁰⁷Rn	¹⁹⁷Rn
87	²⁰⁸Fr
88	²⁰⁹Ra
89	²¹⁰Ac
90	²¹¹Th
91	²¹²Pa