Holmium-168

Properties and data of the isotope ¹⁶⁸Ho.

Content

General data

Name of the isotope:Holmium-168; Ho-168Symbol:¹⁶⁸Ho or 16867HoMass number A:168 (= number of nucleons)Atomic number Z:67 (= number of protons)Neutrons N:101Isotopic mass:167.93552(3) u (atomic weight of Holmium-168)Nuclide mass:167.8987683 u (calculated nuclear mass without electrons)Mass excess:-60.06273 MeVMass defect:1.46391366 u (per nucleus)Nuclear binding energy:1363.62679081 MeV (per nucleus)
8.11682614 MeV (average binding energy per nucleon)Separation energy:S_N = 5.85(3) MeV (first neutron)
S_P = 7.42(7) MeV (first proton)Half-life:2.99(7) minDecay constant λ:0.0038636966586396 s^-1Specific activity α:1.393276977149 × 10⁺¹⁹ Bq g^-1
376561345.17551 Ci g^-1Spin and parity:
(nuclear angular momentum)3+Year of discovery:1960

Radioactive Decay

Half-life T_½ = 2.99(7) min (minutes) respectively 1.794 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁶⁸Er	100 %	2.93(3) MeV

Parent Nuclides

Direct parent isotope is: ¹⁶⁸Dy.

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
^168mHo	59 keV	132(4) s	(6+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 101) and isobaric (same nucleon number A = 168) with Holmium-168. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 101	Isobar A = 168
59	¹⁶⁰Pr
60	¹⁶¹Nd
61	¹⁶²Pm
62	¹⁶³Sm
63	¹⁶⁴Eu	¹⁶⁸Eu
64	¹⁶⁵Gd	¹⁶⁸Gd
65	¹⁶⁶Tb	¹⁶⁸Tb
66	¹⁶⁷Dy	¹⁶⁸Dy
67	¹⁶⁸Ho	¹⁶⁸Ho
68	¹⁶⁹Er	¹⁶⁸Er
69	¹⁷⁰Tm	¹⁶⁸Tm
70	¹⁷¹Yb	¹⁶⁸Yb
71	¹⁷²Lu	¹⁶⁸Lu
72	¹⁷³Hf	¹⁶⁸Hf
73	¹⁷⁴Ta	¹⁶⁸Ta
74	¹⁷⁵W	¹⁶⁸W
75	¹⁷⁶Re	¹⁶⁸Re
76	¹⁷⁷Os	¹⁶⁸Os
77	¹⁷⁸Ir	¹⁶⁸Ir
78	¹⁷⁹Pt	¹⁶⁸Pt
79	¹⁸⁰Au
80	¹⁸¹Hg
81	¹⁸²Tl
82	¹⁸³Pb
83	¹⁸⁴Bi