See also: List of individual Erbium isotopes (and general data sources).
General data
Name of the isotope:Erbium-167; Er-167Symbol:167Er or 16768ErMass number A:167 (= number of nucleons)Atomic number Z:68 (= number of protons)Neutrons N:99Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.4558823529412 (= neutron-proton ratio)Neutron excess (N-Z):31Isotopic mass:166.93205(2) u (atomic weight of Erbium-167)Nuclide mass:166.8947499 u (calculated nuclear mass without electrons)Mass excess:-63.29502 MeVMass defect:1.45787886 u (per nucleus)Nuclear binding energy:1358.00541082 MeV (per nucleus) 8.13176893 MeV (average binding energy per nucleon)Separation energy:SN = 6.43646(18) MeV (first neutron) SP = 7.5088(9) MeV (first proton)Half-life:stableSpin and parity: (nuclear angular momentum)7/2+Magnetic dipole moment:μ(μN) = - 0.56385(12)Charge radius:5.2560(31) femtometer fmYear of discovery:1934
The following table shows the atomic nuclei that are isotonic (same neutron number N = 99) and isobaric (same nucleon number A = 167) with Erbium-167. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.