Osmium-189

Properties and data of the isotope ¹⁸⁹Os.

Contents

General data

Name of the isotope:Osmium-189; Os-189Symbol:¹⁸⁹Os or 18976OsMass number A:189 (= number of nucleons)Atomic number Z:76 (= number of protons)Neutrons N:113Isotopic mass:188.95814(2) u (atomic weight of Osmium-189)Nuclide mass:188.9164522 u (calculated nuclear mass without electrons)Mass excess:-38.99234 MeVMass defect:1.61569794 u (per nucleus)Nuclear binding energy:1505.01293692 MeV (per nucleus)
7.96303141 MeV (average binding energy per nucleon)Separation energy:S_N = 5.9208(4) MeV (first neutron)
S_P = 7.2589(5) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)3/2-Magnetic dipole moment:μ(μ_N) = + 0.659933(4)Charge radius:5..4016(11) femtometer fmYear of discovery:1931

Parent Nuclides

Direct parent isotopes are: ¹⁸⁹Ir, ¹⁸⁹Re.

Occurrence

Comparison of the natural Osmium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Osmium Isotopic mixture	190.23 u	100 %
Isotope ¹⁸⁴Os	183.952489(9) u	0.02(1) %	5.6 × 10¹³ a	0+
Isotope ¹⁸⁶Os	185.95384(1) u	1.59(3) %	2.0(11) × 10¹⁵ a	0+
Isotope ¹⁸⁷Os	186.95575(1) u	1.96(2) %	stable	1/2-
Isotope ¹⁸⁸Os	187.95584(1) u	13.24(8) %	stable	0+
Isotope ¹⁸⁹Os	188.95814(2) u	16.15(5) %	stable	3/2-
Isotope ¹⁹⁰Os	189.95844(2) u	26.26(2) %	stable	0+
Isotope ¹⁹²Os	191.96148(2) u	40.78(19) %	stable	0+

NMR data

Nuclear magnetic properties of the NMR active Nuclide ¹⁸⁹Os

Isotope:¹⁸⁹Os-NMRQuantity:16.15(5) %Spin:3/2-Nuclearmagnetic moment
μ/μ_N:+ 0.659933(4)Nuclear g-factor:g_l = 0.43995533333333Quadrupole moment Q:+ 0.856(28) barn (100 fm²)Resonance frequency:v₀ = 3.3536 at 1 TRelative Sensitivity:0.00244 (H₀ = const.)
0.3938 (v₀ = const.)
[related to ¹H = 1.000]

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
^189mOs	30.82(2) keV	5.81(10) h	9/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 113) and isobaric (same nucleon number A = 189) with Osmium-189. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 113	Isobar A = 189
70	¹⁸³Yb
71	¹⁸⁴Lu
72	¹⁸⁵Hf	¹⁸⁹Hf
73	¹⁸⁶Ta	¹⁸⁹Ta
74	¹⁸⁷W	¹⁸⁹W
75	¹⁸⁸Re	¹⁸⁹Re
76	¹⁸⁹Os	¹⁸⁹Os
77	¹⁹⁰Ir	¹⁸⁹Ir
78	¹⁹¹Pt	¹⁸⁹Pt
79	¹⁹²Au	¹⁸⁹Au
80	¹⁹³Hg	¹⁸⁹Hg
81	¹⁹⁴Tl	¹⁸⁹Tl
82	¹⁹⁵Pb	¹⁸⁹Pb
83	¹⁹⁶Bi	¹⁸⁹Bi
84	¹⁹⁷Po	¹⁸⁹Po
85	¹⁹⁸At
86	¹⁹⁹Rn
87	²⁰⁰Fr
88	²⁰¹Ra