Gadolinium-155

Properties and data of the isotope ¹⁵⁵Gd.

Contents

General data

Name of the isotope:Gadolinium-155; Gd-155Symbol:¹⁵⁵Gd or 15564GdMass number A:155 (= number of nucleons)Atomic number Z:64 (= number of protons)Neutrons N:91Isotopic mass:154.92263(2) u (atomic weight of Gadolinium-155)Nuclide mass:154.8875237 u (calculated nuclear mass without electrons)Mass excess:-72.06969 MeVMass defect:1.366679404 u (per nucleus)Nuclear binding energy:1273.05366475 MeV (per nucleus)
8.21324945 MeV (average binding energy per nucleon)Separation energy:S_N = 6.43524(18) MeV (first neutron)
S_P = 7.6207(8) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)3/2-Magnetic dipole moment:μ(μ_N) = - 0.25723(35)Charge radius:5.1319(41) femtometer fmYear of discovery:1933

Parent Nuclides

Direct parent isotopes are: ¹⁵⁵Tb, ¹⁵⁵Eu.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Gadolinium Isotopic mixture	157.25 u	100 %
Isotope ¹⁵²Gd	151.91980(2) u	0.20(3) %	1.08(8) × 10¹⁴ a	0+
Isotope ¹⁵⁴Gd	153.92087(2) u	2.18(2) %	stable	0+
Isotope ¹⁵⁵Gd	154.92263(2) u	14.80(9) %	stable	3/2-
Isotope ¹⁵⁶Gd	155.92213(2) u	20.47(3) %	stable	0+
Isotope ¹⁵⁷Gd	156.92397(2) u	15.65(4) %	stable	3/2-
Isotope ¹⁵⁸Gd	157.92411(2) u	24.84(8) %	stable	0+
Isotope ¹⁶⁰Gd	159.92706(2) u	21.86(3) %	stable	0+

NMR data

Nuclear magnetic properties of the NMR active Nuclide ¹⁵⁵Gd

Isotope:¹⁵⁵Gd-NMRQuantity:14.80(9) %Spin:3/2-Nuclearmagnetic moment
μ/μ_N:- 0.25723(35)Gyromagnetic ratio γ:0.8273 · 10⁷ rad T^-1 s^-1Nuclear g-factor:g_l = -0.17148666666667Quadrupole moment Q:1.27(3) barn (100 fm²)Line width parameter (factor):l = 21505.33 fm⁴Resonance frequency:v₀ = 1.312 at 1 TRelative Sensitivity:0.00015 (H₀ = const.)
0.1541 (v₀ = const.)
[related to ¹H = 1.000]

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
^155mGd	121.05(19) keV	31.97(27) ms	11/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 91) and isobaric (same nucleon number A = 155) with Gadolinium-155. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 91	Isobar A = 155
52	¹⁴³Te
53	¹⁴⁴I
54	¹⁴⁵Xe
55	¹⁴⁶Cs
56	¹⁴⁷Ba
57	¹⁴⁸La	¹⁵⁵La
58	¹⁴⁹Ce	¹⁵⁵Ce
59	¹⁵⁰Pr	¹⁵⁵Pr
60	¹⁵¹Nd	¹⁵⁵Nd
61	¹⁵²Pm	¹⁵⁵Pm
62	¹⁵³Sm	¹⁵⁵Sm
63	¹⁵⁴Eu	¹⁵⁵Eu
64	¹⁵⁵Gd	¹⁵⁵Gd
65	¹⁵⁶Tb	¹⁵⁵Tb
66	¹⁵⁷Dy	¹⁵⁵Dy
67	¹⁵⁸Ho	¹⁵⁵Ho
68	¹⁵⁹Er	¹⁵⁵Er
69	¹⁶⁰Tm	¹⁵⁵Tm
70	¹⁶¹Yb	¹⁵⁵Yb
71	¹⁶²Lu	¹⁵⁵Lu
72	¹⁶³Hf	¹⁵⁵Hf
73	¹⁶⁴Ta	¹⁵⁵Ta
74	¹⁶⁵W
75	¹⁶⁶Re
76	¹⁶⁷Os
77	¹⁶⁸Ir
78	¹⁶⁹Pt
79	¹⁷⁰Au
80	¹⁷¹Hg