Manganese-56

Properties and data of the isotope ⁵⁶Mn.

Content

General data

Name of the isotope:Manganese-56; Mn-56Symbol:⁵⁶Mn or 5625MnMass number A:56 (= number of nucleons)Atomic number Z:25 (= number of protons)Neutrons N:31Isotopic mass:55.9389029(4) u (atomic weight of Manganese-56)Nuclide mass:55.9251887 u (calculated nuclear mass without electrons)Mass excess:-56.91158 MeVMass defect:0.52533529599999 u (per nucleus)Nuclear binding energy:489.34667621 MeV (per nucleus)
8.7383335 MeV (average binding energy per nucleon)Separation energy:S_N = 7.27044(13) MeV (first neutron)
S_P = 9.0908(4) MeV (first proton)Half-life:2.5789(1) hDecay constant λ:7.466008123187 × 10^-5 s^-1Specific activity α:8.174791378048 × 10⁺¹⁷ Bq g^-1
22094030.751482 Ci g^-1Spin and parity:
(nuclear angular momentum)3+Magnetic dipole moment:μ(μ_N) = +3.240(2)Nuclear g-factor:g_l = 1.08Charge radius:3.7146(52) femtometer fmYear of discovery:1934

Radioactive Decay

Half-life T_½ = 2.5789(1) h (hours) respectively 9.28404 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	⁵⁶Fe	100 %	3.69554(21) MeV

Parent Nuclides

Direct parent isotope is: ⁵⁶Cr.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 31) and isobaric (same nucleon number A = 56) with Manganese-56. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 31	Isobar A = 56
15	⁴⁶P
16	⁴⁷S
17	⁴⁸Cl
18	⁴⁹Ar
19	⁵⁰K	⁵⁶K
20	⁵¹Ca	⁵⁶Ca
21	⁵²Sc	⁵⁶Sc
22	⁵³Ti	⁵⁶Ti
23	⁵⁴V	⁵⁶V
24	⁵⁵Cr	⁵⁶Cr
25	⁵⁶Mn	⁵⁶Mn
26	⁵⁷Fe	⁵⁶Fe
27	⁵⁸Co	⁵⁶Co
28	⁵⁹Ni	⁵⁶Ni
29	⁶⁰Cu	⁵⁶Cu
30	⁶¹Zn	⁵⁶Zn
31	⁶²Ga
32	⁶³Ge
33	⁶⁴As
34	⁶⁵Se
35	⁶⁶Br
36	⁶⁷Kr