Ruthenium-99

Properties and data of the isotope ⁹⁹Ru.

Contents

General data

Name of the isotope:Ruthenium-99; Ru-99Symbol:⁹⁹Ru or 9944RuMass number A:99 (= number of nucleons)Atomic number Z:44 (= number of protons)Neutrons N:55Isotopic mass:98.905934(7) u (atomic weight of Ruthenium-99)Nuclide mass:98.8817977 u (calculated nuclear mass without electrons)Mass excess:-87.62191 MeVMass defect:0.914937788 u (per nucleus)Nuclear binding energy:852.2590599 MeV (per nucleus)
8.60867737 MeV (average binding energy per nucleon)Separation energy:S_N = 7.472(6) MeV (first neutron)
S_P = 8.482(3) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)5/2+Magnetic dipole moment:μ(μ_N) = - 0.641(5)Charge radius:4.4338(42) femtometer fmYear of discovery:1931

Parent Nuclides

Direct parent isotopes are: ⁹⁹Rh, ⁹⁹Tc.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Ruthenium Isotopic mixture	101.07 u	100 %
Isotope ⁹⁶Ru	95.907590(3) u	5.54(14) %	stable	0+
Isotope ⁹⁸Ru	97.90529(5) u	1.87(3) %	stable	0+
Isotope ⁹⁹Ru	98.905934(7) u	12.76(14) %	stable	5/2+
Isotope ¹⁰⁰Ru	99.904214(7) u	12.60(7) %	stable	0+
Isotope ¹⁰¹Ru	100.905577(8) u	17.06(2) %	stable	5/2+
Isotope ¹⁰²Ru	101.904344(8) u	31.55(14) %	stable	0+
Isotope ¹⁰⁴Ru	103.90543(2) u	18.62(27) %	stable	0+

NMR data

Nuclear magnetic properties of the NMR active Nuclide ⁹⁹Ru

Isotope:⁹⁹Ru-NMRQuantity:12.76(14) %Spin:5/2+Nuclearmagnetic moment
μ/μ_N:- 0.641(5)Gyromagnetic ratio γ:- 1.2286 · 10⁷ rad T^-1 s^-1Nuclear g-factor:g_l = -0.2564Quadrupole moment Q:+ 0.079(4) barn (100 fm²)Resonance frequency:v₀ = 1.9553 at 1 TRelative Sensitivity:0.00113 (H₀ = const.)
0.5358 (v₀ = const.)
[related to ¹H = 1.000]

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 55) and isobaric (same nucleon number A = 99) with Ruthenium-99. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 55	Isobar A = 99
30	⁸⁵Zn
31	⁸⁶Ga
32	⁸⁷Ge
33	⁸⁸As
34	⁸⁹Se
35	⁹⁰Br
36	⁹¹Kr	⁹⁹Kr
37	⁹²Rb	⁹⁹Rb
38	⁹³Sr	⁹⁹Sr
39	⁹⁴Y	⁹⁹Y
40	⁹⁵Zr	⁹⁹Zr
41	⁹⁶Nb	⁹⁹Nb
42	⁹⁷Mo	⁹⁹Mo
43	⁹⁸Tc	⁹⁹Tc
44	⁹⁹Ru	⁹⁹Ru
45	¹⁰⁰Rh	⁹⁹Rh
46	¹⁰¹Pd	⁹⁹Pd
47	¹⁰²Ag	⁹⁹Ag
48	¹⁰³Cd	⁹⁹Cd
49	¹⁰⁴In	⁹⁹In
50	¹⁰⁵Sn	⁹⁹Sn
51	¹⁰⁶Sb
52	¹⁰⁷Te
53	¹⁰⁸I
54	¹⁰⁹Xe