Potassium-54

Properties and data of the isotope ⁵⁴K.

Contents

Potassium-54 is a radioisotope of the chemical element potassium, which has 35 neutrons in its atomic nucleus in addition to the element-specific 19 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 54.

The radioactive isotope was first mentioned in a report from 1983; according to this report, potassium-54 was observed and identified during the fragmentation of an iridium template with 10 GeV protons [1].

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

General data

Name of the isotope:Potassium-54; K-54Symbol:⁵⁴K or 5419KMass number A:54 (= number of nucleons)Atomic number Z:19 (= number of protons)Neutrons N:35Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.8421052631579 (= neutron-proton ratio)Neutron excess (N-Z):16Isotopic mass:53.99447(43) u (atomic weight of Potassium-54)Nuclide mass:53.9840472 u (calculated nuclear mass without electrons)Mass excess:-5.15116 MeVMass defect:0.457477668 u (per nucleus)Nuclear binding energy:426.13770288 MeV (per nucleus)
7.89143894 MeV (average binding energy per nucleon)Separation energy:S_N = 0.926(415) MeV (first neutron)
S_P = 19.230(805) MeV (first proton)Half-life:10(5) msDecay constant λ:69.314718055995 s^-1Specific activity α:7.875905581132 × 10⁺²³ Bq g^-1
21286231300357 Ci g^-1Spin and parity:
(nuclear angular momentum)2-Year of discovery:1983

Radioactive Decay

Half-life T_½ = 10(5) ms respectively 1 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	⁵⁴Ca	100 %	20.01(40) MeV
β^-, n ?	⁵³Ca		16.166(402) MeV
β^-, 2n ?	⁵²Ca

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 35) and isobaric (same nucleon number A = 54) with Potassium-54. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 35	Isobar A = 54
17	⁵²Cl
18	⁵³Ar	⁵⁴Ar
19	⁵⁴K	⁵⁴K
20	⁵⁵Ca	⁵⁴Ca
21	⁵⁶Sc	⁵⁴Sc
22	⁵⁷Ti	⁵⁴Ti
23	⁵⁸V	⁵⁴V
24	⁵⁹Cr	⁵⁴Cr
25	⁶⁰Mn	⁵⁴Mn
26	⁶¹Fe	⁵⁴Fe
27	⁶²Co	⁵⁴Co
28	⁶³Ni	⁵⁴Ni
29	⁶⁴Cu	⁵⁴Cu
30	⁶⁵Zn	⁵⁴Zn
31	⁶⁶Ga
32	⁶⁷Ge
33	⁶⁸As
34	⁶⁹Se
35	⁷⁰Br
36	⁷¹Kr
37	⁷²Rb
38	⁷³Sr

External data and identifiers

Adopted Levels, Gammas:NuDat 54K

Literature and References

[1] - M. Langevin, C. Détraz, D. Guillemaud-Mueller et al.:
⁵³K, ⁵⁴K and ⁵³Ca: Three new neutron rich isotopes.
In: Physics Letters B, 130, 5, (1983), DOI 10.1016/0370-2693(83)91135-8.