Krypton-85m1

Properties and data of the isotope ^85m1Kr.

Contents

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

General data

Name of the isotope:Krypton-85m1; Kr-85m1Symbol:^85m1Kr or 85m136KrMass number A:85 (= number of nucleons)Atomic number Z:36 (= number of protons)Neutrons N:49Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.3611111111111 (= neutron-proton ratio)Neutron excess (N-Z):13Excitation energy:304.871(20) keVIsotopic mass:84.9125273(21) u (atomic weight of Krypton-85m1)Nuclide mass:84.8927792 u (calculated nuclear mass without electrons)Mass excess:-81.4803 MeVMass defect:0.79375473600001 u (per nucleus)Nuclear binding energy:739.37777406 MeV (per nucleus)
8.69856205 MeV (average binding energy per nucleon)Half-life:4.480(8) hDecay constant λ:4.295124430288 × 10^-5 s^-1Specific activity α:3.07926718216 × 10⁺¹⁷ Bq g^-1
8322343.7355703 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-Magnetic dipole moment:μ(μ_N) = +0.632(2)Nuclear g-factor:g_l = 1.264

Radioactive Decay

Half-life T_½ = 4.480(8) h (hours) respectively 1.6138 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	⁸⁵Kr	21.2(5) %
β^-	⁸⁵Rb	78.8(5) %

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
⁸⁵Kr		10.739(14) a	9/2+
^85m2Kr	1991.8(2) keV	1.82(5) μs	(17/2+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 49) and isobaric (same nucleon number A = 85) with Krypton-85m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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