Molybdenum-91m

Properties and data of the isotope ^91mMo.

Contents

See also: List of individual Molybdenum isotopes (and general data sources).

General data

Name of the isotope:Molybdenum-91m; Mo-91mSymbol:^91mMo or 91m42MoMass number A:91 (= number of nucleons)Atomic number Z:42 (= number of protons)Neutrons N:49Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.1666666666667 (= neutron-proton ratio)Neutron excess (N-Z):7Excitation energy:653.01(9) keVIsotopic mass:90.911745(7) u (atomic weight of Molybdenum-91m)Nuclide mass:90.8887057 u (calculated nuclear mass without electrons)Mass excess:-82.209 MeVMass defect:0.84148722800001 u (per nucleus)Nuclear binding energy:783.84030396 MeV (per nucleus)
8.61362971 MeV (average binding energy per nucleon)Half-life:64.6(6) sDecay constant λ:0.010729832516408 s^-1Specific activity α:7.179618090815 × 10⁺¹⁹ Bq g^-1
1940437321.842 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-

Radioactive Decay

Half-life T_½ = 64.6(6) s respectively 6.46 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁹¹Nb	50.0(16) %
Iso	⁹¹Mo	50.0(16) %

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
⁹¹Mo		15.49(1) min	9/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 49) and isobaric (same nucleon number A = 91) with Molybdenum-91m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 49	Isobar A = 91
27	⁷⁶Co
28	⁷⁷Ni
29	⁷⁸Cu
30	⁷⁹Zn
31	⁸⁰Ga
32	⁸¹Ge
33	⁸²As	⁹¹As
34	⁸³Se	⁹¹Se
35	⁸⁴Br	⁹¹Br
36	⁸⁵Kr	⁹¹Kr
37	⁸⁶Rb	⁹¹Rb
38	⁸⁷Sr	⁹¹Sr
39	⁸⁸Y	⁹¹Y
40	⁸⁹Zr	⁹¹Zr
41	⁹⁰Nb	⁹¹Nb
42	⁹¹Mo	⁹¹Mo
43	⁹²Tc	⁹¹Tc
44	⁹³Ru	⁹¹Ru
45	⁹⁴Rh	⁹¹Rh
46	⁹⁵Pd	⁹¹Pd
47	⁹⁶Ag
48	⁹⁷Cd
49	⁹⁸In
50	⁹⁹Sn