Europium-151

Properties and data of the isotope ¹⁵¹Eu.

Contents

General Data

Radioactive Decay

Parent Nuclides

NMR Data

Isotones und Isobares

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

General data

Name of the isotope:Europium-151; Eu-151Symbol:¹⁵¹Eu or 15163EuMass number A:151 (= number of nucleons)Atomic number Z:63 (= number of protons)Neutrons N:88Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.3968253968254 (= neutron-proton ratio)Neutron excess (N-Z):25Isotopic mass:150.9198566(13) u (atomic weight of Europium-151)Nuclide mass:150.8852988 u (calculated nuclear mass without electrons)Mass excess:-74.6531 MeVMass defect:1.335633024 u (per nucleus)Nuclear binding energy:1244.13414806 MeV (per nucleus)
8.23929899 MeV (average binding energy per nucleon)Separation energy:S_N = 7.932(6) MeV (first neutron)
S_P = 4.8907(5) MeV (first proton)Half-life:1.7 × 10¹⁸ yearsDecay constant λ:1.292914877040 × 10^-26 s^-1Specific activity α:5.159106002116 × 10^-5 Bq g^-1
1.39435297354 × 10^-15 Ci g^-1Spin and parity:
(nuclear angular momentum)5/2+Magnetic dipole moment:μ(μ_N) = + 3.4717(6)Charge radius:5.0522(46) femtometer fmYear of discovery:1933

Radioactive Decay

Half-life T_½ = 1.7 × 10¹⁸ years respectively 5.36112 × 10²⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁴⁷Pm	?	1.9640(11) MeV

Parent Nuclides

Direct parent isotopes are: ¹⁵¹Gd, ¹⁵¹Sm.

Occurrence

Comparison of the natural Europium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Europium Isotopic mixture	151.964 u	100 %
Isotope ¹⁵¹Eu	150.9198566(13) u	47.81(6) %	1.7 × 10¹⁸ years	5/2+
Isotope ¹⁵³Eu	152.92124(2) u	52.19(6) %	stable	5/2+

NMR data

Nuclear magnetic properties and parameters of the NMR active Nuclide ¹⁵¹Eu

Isotope:¹⁵¹Eu-NMRQuantity:47.81(6) %Spin:5/2+Nuclearmagnetic moment
μ/μ_N:+ 3.4717(6)Gyromagnetic ratio γ:6.5477 · 10⁷ rad T^-1 s^-1
10.42099 MHz T^-1Nuclear g-factor:g_l = 1.38868Quadrupole moment Q:+0.903(10) barn (100 fm²)Line width parameter (factor):l = 2609.31 fm⁴Resonance frequency:v₀ = 10.5856 MHz at 1 TRelative Sensitivity:[related to ¹H = 1.000]:
0.17929 (H₀ = const.)
2.9006 (v₀ = const.)

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
^151mEu	196.245(10)	58.9(5) µs	11/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 88) and isobaric (same nucleon number A = 151) with Europium-151. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 88	Isobar A = 151
49	¹³⁷In
50	¹³⁸Sn
51	¹³⁹Sb
52	¹⁴⁰Te
53	¹⁴¹I
54	¹⁴²Xe
55	¹⁴³Cs	¹⁵¹Cs
56	¹⁴⁴Ba	¹⁵¹Ba
57	¹⁴⁵La	¹⁵¹La
58	¹⁴⁶Ce	¹⁵¹Ce
59	¹⁴⁷Pr	¹⁵¹Pr
60	¹⁴⁸Nd	¹⁵¹Nd
61	¹⁴⁹Pm	¹⁵¹Pm
62	¹⁵⁰Sm	¹⁵¹Sm
63	¹⁵¹Eu	¹⁵¹Eu
64	¹⁵²Gd	¹⁵¹Gd
65	¹⁵³Tb	¹⁵¹Tb
66	¹⁵⁴Dy	¹⁵¹Dy
67	¹⁵⁵Ho	¹⁵¹Ho
68	¹⁵⁶Er	¹⁵¹Er
69	¹⁵⁷Tm	¹⁵¹Tm
70	¹⁵⁸Yb	¹⁵¹Yb
71	¹⁵⁹Lu	¹⁵¹Lu
72	¹⁶⁰Hf
73	¹⁶¹Ta
74	¹⁶²W
75	¹⁶³Re
76	¹⁶⁴Os
77	¹⁶⁵Ir
78	¹⁶⁶Pt