See also: List of individual Calcium isotopes (and general data sources).
General data
Name of the isotope:Calcium-41; Ca-41Symbol:41Ca or 4120CaMass number A:41 (= number of nucleons)Atomic number Z:20 (= number of protons)Neutrons N:21Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.05 (= neutron-proton ratio)Neutron excess (N-Z):1Isotopic mass:40.96227792(15) u (atomic weight of Calcium-41)Nuclide mass:40.9513065 u (calculated nuclear mass without electrons)Mass excess:-35.13789 MeVMass defect:0.376185956 u (per nucleus)Nuclear binding energy:350.4149609 MeV (per nucleus) 8.54670636 MeV (average binding energy per nucleon)Separation energy:SN = 8.36282(14) MeV (first neutron) SP = 8.89137(15) MeV (first proton)Half-life:9.94(15) × 104 yearsDecay constant λ:2.211221498079 × 10-13 s-1Specific activity α:3250865867.1227 Bq g-1 0.087861239651965 Ci g-1Spin and parity: (nuclear angular momentum)7/2-Magnetic dipole moment:μ(μN) = -1.59443(7)Quadrupole moment Q:- 0.0665(18) barn (100 fm2)Nuclear g-factor:gl = -0.45555142857143Charge radius:3.4780(19) femtometer fmMirror nucleus:Scandium-41Year of discovery:1939
Radioactive Decay
Half-life T½ = 9.94(15) × 104 years respectively 3.13468 × 1012 seconds s.
Comparison of the natural Calcium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
Atomic Mass ma
Quantity
Half-life
Spin
Calcium Isotopic mixture
40.078 u
100 %
Isotope 40Ca
39.9625909(2) u
96.941(156) %
stable
0+
Isotope 41Ca
40.96227792(15) u
[trace]
9.94(15) × 104 years
7/2-
Isotope 42Ca
41.958618(1) u
0.647(23) %
stable
0+
Isotope 44Ca
43.955482(2) u
2.086(110) %
stable
0+
Isotope 46Ca
45.95369(2) u
0.004(3) %
stable
0+
Isotope 48Ca
47.952522654(19) u
0.187(21) %
5.3 × 1019 years
0+
Isotope 43Ca
42.95876638(24) u
0.135(10) %
stable
7/2-
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 21) and isobaric (same nucleon number A = 41) with Calcium-41. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
