Nobelium-259

Properties and data of the isotope ²⁵⁹No.

Contents

General data

Name of the isotope:Nobelium-259; No-259Symbol:²⁵⁹No or 259102NoMass number A:259 (= number of nucleons)Atomic number Z:102 (= number of protons)Neutrons N:157Isotopic mass:259.100998(7) u (atomic weight of Nobelium-259)Nuclide mass:259.0450513 u (calculated nuclear mass without electrons)Mass excess:94.07903 MeVMass defect:2.057547076 u (per nucleus)Nuclear binding energy:1916.59275601 MeV (per nucleus)
7.39997203 MeV (average binding energy per nucleon)Separation energy:S_N = 5.47(10) MeV (first neutron)
S_P = 4.897(8) MeV (first proton)Half-life:58(5) minDecay constant λ:0.00019918022429883 s^-1Specific activity α:4.631240800159 × 10⁺¹⁷ Bq g^-1
12516867.027459 Ci g^-1Spin and parity:
(nuclear angular momentum)(9/2+)Year of discovery:1973

Radioactive Decay

Half-life T_½ = 58(5) min (minutes) respectively 3.480 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy
α	²⁵⁵Fm	75(4) %	7.854(5) MeV
EE/β⁺	²⁵⁹Md	25(4) %	0.45(20) MeV
SF	div.	< 10 %

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Nobelium Isotopic mixture	259.101033 u	100 %
Isotope ²⁵⁹No	259.100998(7) u	100 %	58(5) min	(9/2+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 157) and isobaric (same nucleon number A = 259) with Nobelium-259. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 157	Isobar A = 259
97	²⁵⁴Bk
98	²⁵⁵Cf
99	²⁵⁶Es
100	²⁵⁷Fm	²⁵⁹Fm
101	²⁵⁸Md	²⁵⁹Md
102	²⁵⁹No	²⁵⁹No
103	²⁶⁰Lr	²⁵⁹Lr
104	²⁶¹Rf	²⁵⁹Rf
105	²⁶²Db	²⁵⁹Db
106	²⁶³Sg	²⁵⁹Sg
107	²⁶⁴Bh
108	²⁶⁵Hs
109	²⁶⁶Mt
110	²⁶⁷Ds