Manganese-46

Properties and data of the isotope ⁴⁶Mn.

Content

General data

Name of the isotope:Manganese-46; Mn-46Symbol:⁴⁶Mn or 4625MnMass number A:46 (= number of nucleons)Atomic number Z:25 (= number of protons)Neutrons N:21Isotopic mass:45.98651(43) u (atomic weight of Manganese-46)Nuclide mass:45.9727958 u (calculated nuclear mass without electrons)Mass excess:-12.56585 MeVMass defect:0.391079036 u (per nucleus)Nuclear binding energy:364.28777556 MeV (per nucleus)
7.91929947 MeV (average binding energy per nucleon)Separation energy:S_N = 15.39(56) MeV (first neutron)
S_P = 0.34(40) MeV (first proton)Half-life:36.2(4) msDecay constant λ:19.147712170164 s^-1Specific activity α:2.562449329650 × 10⁺²³ Bq g^-1
6925538728784.1 Ci g^-1Spin and parity:
(nuclear angular momentum)(4+)Isobaric spin: 2Mirror nucleus:Scandium-46Year of discovery:1987

Radioactive Decay

Half-life T_½ = 36.2(4) ms respectively 3.62 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β⁺	⁴⁶Cr	43 %	16.90(40) MeV
EE, p	⁴⁵V	57.0(8) %

Parent Nuclides

Direct parent isotope is: ⁴⁶Fe.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^46mMn	150(100) keV	1 ms	1-~

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 21) and isobaric (same nucleon number A = 46) with Manganese-46. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 21	Isobar A = 46
9	³⁰F
10	³¹Ne
11	³²Na
12	³³Mg
13	³⁴Al
14	³⁵Si
15	³⁶P	⁴⁶P
16	³⁷S	⁴⁶S
17	³⁸Cl	⁴⁶Cl
18	³⁹Ar	⁴⁶Ar
19	⁴⁰K	⁴⁶K
20	⁴¹Ca	⁴⁶Ca
21	⁴²Sc	⁴⁶Sc
22	⁴³Ti	⁴⁶Ti
23	⁴⁴V	⁴⁶V
24	⁴⁵Cr	⁴⁶Cr
25	⁴⁶Mn	⁴⁶Mn
26	⁴⁷Fe	⁴⁶Fe
27	⁴⁸Co	⁴⁶Co
28	⁴⁹Ni