Scandium-44

Properties and data of the isotope ⁴⁴Sc.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

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

General data

Name of the isotope:Scandium-44; Sc-44Symbol:⁴⁴Sc or 4421ScMass number A:44 (= number of nucleons)Atomic number Z:21 (= number of protons)Neutrons N:23Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.0952380952381 (= neutron-proton ratio)Neutron excess (N-Z):2Isotopic mass:43.9594029(19) u (atomic weight of Scandium-44)Nuclide mass:43.9478829 u (calculated nuclear mass without electrons)Mass excess:-37.81596 MeVMass defect:0.40421584000001 u (per nucleus)Nuclear binding energy:376.52462966 MeV (per nucleus)
8.55737795 MeV (average binding energy per nucleon)Separation energy:S_N = 9.6992(25) MeV (first neutron)
S_P = 6.6961(17) MeV (first proton)Half-life:3.97(4) hDecay constant λ:4.849896309543 × 10^-5 s^-1Specific activity α:6.792269472594 × 10⁺¹⁷ Bq g^-1
18357485.061067 Ci g^-1Spin and parity:
(nuclear angular momentum)2+Magnetic dipole moment:μ(μ_N) = + 2.498(5)Quadrupole moment Q:0.16(4) barn (100 fm²)Nuclear g-factor:g_l = 1.249Charge radius:3.5432(16) femtometer fmMirror nucleus:Vanadium-44Year of discovery:1937

Radioactive Decay

Half-life T_½ = 3.97(4) h (hours) respectively 1.4292 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC β⁺	⁴⁴Ca	100 %	3.6527(18) MeV

Parent Nuclides

Direct parent isotope is: ⁴⁴Ti.

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
^44m1Sc	67.8679(14) keV	154.8(8) ns	1-
^44m2Sc	146.1914(20) keV	51.0(3) μs	0-
^44m3Sc	271.24(1) keV	58.61(10) h	6+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 23) and isobaric (same nucleon number A = 44) with Scandium-44. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 23	Isobar A = 44
10	³³Ne
11	³⁴Na
12	³⁵Mg
13	³⁶Al
14	³⁷Si	⁴⁴Si
15	³⁸P	⁴⁴P
16	³⁹S	⁴⁴S
17	⁴⁰Cl	⁴⁴Cl
18	⁴¹Ar	⁴⁴Ar
19	⁴²K	⁴⁴K
20	⁴³Ca	⁴⁴Ca
21	⁴⁴Sc	⁴⁴Sc
22	⁴⁵Ti	⁴⁴Ti
23	⁴⁶V	⁴⁴V
24	⁴⁷Cr	⁴⁴Cr
25	⁴⁸Mn	⁴⁴Mn
26	⁴⁹Fe
27	⁵⁰Co
28	⁵¹Ni

External data and identifiers

Adopted Levels, Gammas:NuDat 44Sc

Literature and References

[1] - Simon Ferguson, Hans-Sonke Jans, Melinda Wuest, Terence Riauka, Frank Wuest:
Comparison of scandium-44 g with other PET radionuclides in pre-clinical PET phantom imaging.
In: EJNMMI Physics, (2019), DOI 10.1186/s40658-019-0260-0.

[2] - Brett A. Vaughn, Shin Hye Ahn, Eduardo Aluicio-Sarduy, Justin Devaraj, Aeli P. Olson, Jonathan Engleb, Eszter Boros:
Chelation with a twist: a bifunctional chelator to enable room temperature radiolabeling and targeted PET imaging with scandium-44.
In: Chemical Science, (2019), DOI 10.1039/C9SC04655K.