Osmium-177

Properties and data of the isotope ¹⁷⁷Os.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Osmium-177; Os-177Symbol:¹⁷⁷Os or 17776OsMass number A:177 (= number of nucleons)Atomic number Z:76 (= number of protons)Neutrons N:101Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.3289473684211 (= neutron-proton ratio)Neutron excess (N-Z):25Isotopic mass:176.954958(16) u (atomic weight of Osmium-177)Nuclide mass:176.9132702 u (calculated nuclear mass without electrons)Mass excess:-41.95635 MeVMass defect:1.514900948 u (per nucleus)Nuclear binding energy:1411.12114366 MeV (per nucleus)
7.97243584 MeV (average binding energy per nucleon)Separation energy:S_N = 7.93(3) MeV (first neutron)
S_P = 4.18(3) MeV (first proton)Half-life:3.0(2) minDecay constant λ:0.0038508176697775 s^-1Specific activity α:1.31762309280 × 10⁺¹⁹ Bq g^-1
356114349.40622 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-Year of discovery:1970

Radioactive Decay

Half-life T_½ = 3.0(2) min (minutes) respectively 1.80 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁷⁷Re	100 %	4.31(3) MeV

Parent Nuclides

Direct parent isotopes are: ¹⁸¹Pt, ¹⁷⁷Ir.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 101) and isobaric (same nucleon number A = 177) with Osmium-177. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 101	Isobar A = 177
57	¹⁵⁸La
58	¹⁵⁹Ce
59	¹⁶⁰Pr
60	¹⁶¹Nd
61	¹⁶²Pm
62	¹⁶³Sm
63	¹⁶⁴Eu
64	¹⁶⁵Gd
65	¹⁶⁶Tb
66	¹⁶⁷Dy
67	¹⁶⁸Ho
68	¹⁶⁹Er	¹⁷⁷Er
69	¹⁷⁰Tm	¹⁷⁷Tm
70	¹⁷¹Yb	¹⁷⁷Yb
71	¹⁷²Lu	¹⁷⁷Lu
72	¹⁷³Hf	¹⁷⁷Hf
73	¹⁷⁴Ta	¹⁷⁷Ta
74	¹⁷⁵W	¹⁷⁷W
75	¹⁷⁶Re	¹⁷⁷Re
76	¹⁷⁷Os	¹⁷⁷Os
77	¹⁷⁸Ir	¹⁷⁷Ir
78	¹⁷⁹Pt	¹⁷⁷Pt
79	¹⁸⁰Au	¹⁷⁷Au
80	¹⁸¹Hg	¹⁷⁷Hg
81	¹⁸²Tl	¹⁷⁷Tl
82	¹⁸³Pb
83	¹⁸⁴Bi