See also: List of individual Ruthenium isotopes (and general data sources).
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:55Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.25 (= neutron-proton ratio)Neutron excess (N-Z):11Isotopic 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:SN = 7.472(6) MeV (first neutron) SP = 8.482(3) MeV (first proton)Half-life:stableSpin and parity: (nuclear angular momentum)5/2+Magnetic dipole moment:μ(μN) = - 0.641(5)Charge radius:4.4338(42) femtometer fmYear of discovery:1931
Comparison of the natural Ruthenium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
Atomic Mass ma
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 and parameters of the NMR active Nuclide99Ru
Isotope:99Ru-NMRQuantity:12.76(14) %Spin:5/2+Nuclearmagnetic moment μ/μN:- 0.641(5)Gyromagnetic ratio γ:0 · 107 rad T-1 s-1 0.00000 MHz T-1Nuclear g-factor:gl = -0.2564Quadrupole moment Q:+0.079(4) barn (100 fm2)Line width parameter (factor):l = 19.97 fm4Resonance frequency:v0 = 1.9553 MHz at 1 TRelative Sensitivity:[related to 1H = 1.000]: 0.00113 (H0 = const.) 0.5358 (v0 = const.)
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.
