No 102

Nobelium (No)

actinide
Period: 7 Block: s

Solid

Standard Atomic Weight

[259]

Electron configuration

[Rn] 7s2 5f14

Melting point

826.85 °C (1100 K)

Boiling point

N/A

Density

9900 kg/m³

Oxidation states

+2, +3

Electronegativity (Pauling)

1.3

Ionization energy (1st)

Discovery year

1957

Atomic radius

N/A

Details

Name origin Named in honor of Alfred Nobel, who invented dynamite and founded Nobel prize.
Discovery country Sweden
Discoverers Nobel Institute for Physics

Nobelium is a synthetic actinide with atomic number 102. It is produced only in particle-accelerator experiments and is studied in atom-at-a-time quantities. Its longest-lived confirmed isotopes have half-lives of only minutes, so no macroscopic sample or ordinary material application exists. Chemically, nobelium is notable because the +2 oxidation state is unusually stable for an actinide, in contrast to the more common +3 state of many neighboring elements.

Nobelium does not occur naturally in the Earth’s crust. It was first synthesized in 1966 by Russian scientists from the Joint Institute for Nuclear Research (JINR) in Dubna, Russia under Georgi Flerov. Earlier claims to have synthesized “nobelium” beginning in 1957 were shown to be erroneous. This element was originally named for Alfred Nobel (Fig. IUPAC.102.1), the inventor of dynamite and founder of the Nobel prizes. The name was later retained because of its widespread use throughout the scientific literature [636], [638]. There are no uses for isotopes of nobelium outside of scientific research.

Nobelium is named after Alfred Nobel.

In 1957, a group of scientists working at the Nobel Institute of Physics in Stockhlom, Sweden, announced the discovery of a new element. They produced this new element, which they named nobelium, by bombarding a target of curium-244 with ions of carbon-13 with a device called a cyclotron. The isotope they created had a half-life of 10 minutes. In 1958, another group of scientists, Albert Ghiorso, Glenn T. Seaborg, Torbørn Sikkeland and John R. Walton, working at the Lawrence Radiation Laboratory in Berkeley, California, attempted to confirm the Nobel Institute's discovery. They were unable to produce any isotope of nobelium with a half-life of 10 minutes, but were able to produce nobelium-254, with a half-life of three seconds, by bombarding curium-246 with carbon-12. A third group, working at the Joint Institute for Nuclear Research in Dubna, Russia, also could not duplicate the Nobel Institute's work but were able to confirm the Berkeley group's work. Credit for discovering nobelium was eventually given to the scientists working at Lawrence Radiation Laboratory, who decided to keep the name nobelium. Today, the Lawrence Radiation Laboratory is known as the Lawrence Berkeley Laboratory. Nobelium's most stable isotope, nobelium-259, has a half-life of about 58 minutes. It decays into fermium-255 through alpha decay, into mendelevium-259 through electron capture or through spontaneous fission.

Named after Alfred Nobel, inventor of dynamite. Nobelium was unambiguously discovered and identified in April 1958 at Berkeley by A. Ghiorso, T. Sikkeland, J.R. Walton, and G.T. Seaborg, who used a new double-recoil technique. A heavy-ion linear accelerator (HILAC) was used to bombard a thin target of curium (95%244Cm and 4.5% 246Cm) with 12C ions to produce 102No according to the 246Cm(12C, 4n) reaction.

In 1957 workers in the United States, Britain, and Sweden announced the discovery of an isotope of element 102 with a 10-minute half-life at 8.5 MeV, as a result of bombarding 244Cm with 13C nuclei. On the basis of this experiment, the name nobelium was assigned and accepted by the Commission on Atomic Weights of the International Union of Pure and Applied Chemistry.

The acceptance of the name was premature because both Russian and American efforts now completely rule out the possibility of any isotope of Element 102 having a half-life of 10 min in the vicinity of 8.5 MeV. Early work in 1957 on the search for this element, in Russia at the Kurchatov Institute, was marred by the assignment of 8.9 +/- 0.4 MeV alpha radiation with a half-life of 2 to 40 sec, which was too indefinite to support discovery claims.

Confirmatory experiments at Berkeley in 1966 have shown the existence of 254102 with a 55-s half-life, 252102 with a 2.3-s half-life, and 257102 with a 23-s half-life.

Following tradition giving the right to name an element to the discoverer(s), the Berkeley group in 1967, suggested that the hastily given name nobelium along with the symbol No , be retained.

Images

Properties

Physical

Van der Waals radius 246 pm
Density
Phase at STP solid
Melting point 826.85 °C

Chemical

Electronegativity (Pauling) 1.3
Electron affinity
Ionization energy (1st)
Ionization energy (2nd)
Ionization energy (3rd)
Ionization energy (4th)
Ionization energy (5th)
Oxidation states +2, +3
Valence electrons 3
Electron configuration
Electron configuration (semantic)

Thermodynamic

Heat of sublimation 4.042079 eV
Heat of atomization 4.042079 eV

Nuclear

Stable isotopes 0
Mass number (most stable) 259
Discovery year 1957

Abundance

N/A

Reactivity

N/A

Crystal Structure

N/A

Electronic Structure

Electrons per shell 2, 8, 18, 32, 32, 8, 2

Identifiers

CAS number 10028-14-5
Term symbol
InChI InChI=1S/No
InChI Key ORQBXQOJMQIAOY-UHFFFAOYSA-N

Electron Configuration Measured

Ion charge
Protons 102
Electrons 102
Charge Neutral
Configuration No: 5f¹⁴ 7s²
Electron configuration
Measured
[Rn] 5f¹⁴ 7s²
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 7s²
Orbital diagram
1s
2/2
2s
2/2
2p
6/6
3s
2/2
3p
6/6
4s
2/2
3d
10/10
4p
6/6
5s
2/2
4d
10/10
5p
6/6
6s
2/2
4f
14/14
5d
10/10
6p
6/6
7s
2/2
5f
14/14
Total electrons: 102 Unpaired: 0

Atomic model

Protons 102
Neutrons 152
Electrons 102
Mass number 254
Stability Radioactive

Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.

Schematic atomic model, not to scale.

Atomic Fingerprint

Emission / Absorption Spectrum

0 / 0 (0 with intensity)
Measured
Emission Visible: 380–750 nm

Isotope Distribution

No stable isotopes.

Mass numberAtomic mass (u)Natural abundanceHalf-life
251 Radioactive251.08894 ± 0.00012N/A800 ms
260 Radioactive260.10264 ± 0.00022N/A106 ms
259 Radioactive259.10103 ± 0.00011N/A58 minutes
249 Radioactive249.0878 ± 0.0003N/A57 us
254 Radioactive254.090956 ± 0.000011N/A51.2 seconds
Measured

Phase / State

1 atm / 101.325 kPa
Solid 25 °C (298.15 K)

Reason: 801.9 °C below sublimation point (826.85 °C)

Sublimation point 826.85 °C
0 K Current temperature: 25 °C 6000 K
Phase timeline

Schematic, not to scale

Solid
Gas
Sublimation
25°C
Solid
Liquid
Gas
Current

Phase transition points

Sublimation point Literature
826.85 °C
Current phase Calculated
Solid

Transition energies

Heat of sublimation Literature
4.042079 eV

Energy required to sublime 1 mol at sublimation point

Density

Reference density Literature
9900 kg/m³

At standard conditions

Current density Calculated
9900 kg/m³

At standard conditions

Atomic Spectra

Showing 10 of 102 Atomic Spectra. Sorted by ion charge (ascending).

Levels Holdings ?

IonChargeLevels
No I 02
No II +12
No III +22
No IV +32
No V +42
No VI +52
No VII +62
No VIII +72
No IX +82
No X +92
NIST Levels Holdings →
102 No 259

Nobelium — Atomic Orbital Visualizer

[Rn]7s25f14
Energy levels 2 8 18 32 32 8 2
Oxidation states +2, +3
HOMO 7s n=7 · l=0 · m=0
Nobelium — Atomic Orbital Visualizer Preview
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102 No 259

Nobelium — Crystal Structure Visualizer

Crystal structure data not available

Ionic Radii

ChargeCoordinationSpinRadius
+26N/A110.00000000000001 pm
+39N/A108.5 pm

Compounds

No
259.101 u

Isotopes (5)

Ten isotopes are now recognized, one of which 255102 has a half-life of 3 minutes.

Mass numberAtomic mass (u)Natural abundanceHalf-lifeDecay mode
251 Radioactive251.08894 ± 0.00012N/A800 ms
α =83±1.6%β+ ?SF<0.3%
260 Radioactive260.10264 ± 0.00022N/A106 ms
SF =100%
259 Radioactive259.10103 ± 0.00011N/A58 minutes
α =75±0.4%ε =25±0.4%SF<10%
249 Radioactive249.0878 ± 0.0003N/A57 us
β+ ?α ?
254 Radioactive254.090956 ± 0.000011N/A51.2 seconds
α =90±0.1%β+ =10±0.1%SF =0.17±0.2%
251 Radioactive
Atomic mass (u) 251.08894 ± 0.00012
Natural abundance N/A
Half-life 800 ms
Decay mode
α =83±1.6%β+ ? +1
260 Radioactive
Atomic mass (u) 260.10264 ± 0.00022
Natural abundance N/A
Half-life 106 ms
Decay mode
SF =100%
259 Radioactive
Atomic mass (u) 259.10103 ± 0.00011
Natural abundance N/A
Half-life 58 minutes
Decay mode
α =75±0.4%ε =25±0.4% +1
249 Radioactive
Atomic mass (u) 249.0878 ± 0.0003
Natural abundance N/A
Half-life 57 us
Decay mode
β+ ?α ?
254 Radioactive
Atomic mass (u) 254.090956 ± 0.000011
Natural abundance N/A
Half-life 51.2 seconds
Decay mode
α =90±0.1%β+ =10±0.1% +1

Extended Properties

Covalent Radii (Extended)

Covalent radius (Pyykkö)  

Van der Waals Radii

UFF  

Numbering Scales

Mendeleev
Pettifor
Glawe

Electronegativity Scales

Ghosh

Polarizability & Dispersion

Dipole polarizability  
Dipole polarizability (unc.)  

Phase Transitions & Allotropes

Melting point1100.15 K

Oxidation State Categories

+2 extended
+3 main

Advanced Reference Data

Crystal Radii Detail (2)
ChargeCNSpinrcrystal (pm)Origin
2VI124estimated,
3IX122.5
Isotope Decay Modes (39)
IsotopeModeIntensity
248SF
249B+
249A
250SF100%
250A
250B+
251A83%
251B+
251SF0.3%
252A67.6%

Additional Data

References

(9)
2 Atomic Mass Data Center (AMDC), International Atomic Energy Agency (IAEA)
No

The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.

3 IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW)
Nobelium

Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.

4 IUPAC Periodic Table of the Elements and Isotopes (IPTEI)

The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.

License note: Copyright (c) 2020 International Union of Pure and Applied Chemistry. The International Union of Pure and Applied Chemistry (IUPAC) contribution within Pubchem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.
5 Jefferson Lab, U.S. Department of Energy
Nobelium

Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/

License note: Please see citation and linking information: https://education.jlab.org/faq/index.html
6 Los Alamos National Laboratory, U.S. Department of Energy
Nobelium

The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.

7 NIST Physical Measurement Laboratory
Nobelium

The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database

8 PubChem Elements
Nobelium

This section provides all form of data related to element Nobelium.

9 PubChem Elements
Nobelium

The element property data was retrieved from publications.

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