104 Rf (267)

Rutherfordium

Transition metal * Rutherfordium solid Radioactivity

[Rn] 5f¹⁴ 6d² 7s² · 2 · 8 · 18 · 32 · 32 · 10 · 2

The first transactinide — the element where the sixth period of the d-block genuinely begins. Rutherfordium was the first whose chemistry could be studied, confirming that it behaves like hafnium rather than like an actinide.

3D model

Bohr model: nucleus and electron shells from the real configuration. Valence electrons are highlighted.

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Atomic properties

Atomic number
104
Atomic mass
267 а.е.м.
№15 / 118
Electron configuration
[Rn] 5f¹⁴ 6d² 7s²
Electrons per shell
2 · 8 · 18 · 32 · 32 · 10 · 2
Block
d-block
Group
Titanium group
Period
7
Electronegativity (Pauling)
no data
Electronegativity (Allen)
no data
Atomic radius
no data
Covalent radius
157 pm
№52 / 118
Van der Waals radius
no data
Ionisation energy 1
580 kJ/mol
№91 / 118
Electron affinity
no data
Common oxidation states
+4
Oxidation states
+4

Physical properties

State at 25 °C
solid
Density
17 g/cm³
№17 / 118
Melting point
2 400 K · 2 126.9 °C
№12 / 111
Boiling point
5 800 K · 5 526.9 °C
№3 / 107
Speed of sound
no data

Thermal properties

Heat of fusion
no data
Heat of vaporisation
no data
Specific heat capacity
no data
Thermal conductivity
no data

Mechanical properties

Young's modulus
no data
Shear modulus
no data
Bulk modulus
no data
Poisson ratio
no data
Mohs hardness
no data
Brinell hardness
no data

Electrical and magnetic properties

Electrical resistivity
no data
Magnetic ordering
no data
Curie point
no data
Néel point
no data
Superconducting point
no data

Crystal structure

Crystal structure
hexagonal close-packed (hcp)
Lattice constants
no data

Abundance

In the crust
does not occur
In the ocean
does not occur
In the universe
does not occur
In the human body
does not occur

Isotopes

Isotope Abundance Half-life Decay mode
265Rf 1.1 min СД
267Rf 1.3 h СД

Rutherfordium-267, half-life about 1.3 hours, is the longest-lived. Chemistry is done on rutherfordium-261 at 68 seconds.

Discovery

Year of discovery
1964
№16 / 108
Discovered by
Dubna and Berkeley
Where
USSR and USA
Origin of the name
after Ernest Rutherford

History

Dubna claimed the synthesis in 1964 and proposed kurchatovium; Berkeley claimed it in 1969 and proposed rutherfordium. The dispute ran for decades, and IUPAC settled on rutherfordium only in 1997.

Where it occurs

Absent from nature.

How it is produced

By nuclear fusion: californium-249 bombarded with carbon-13 ions, or plutonium with neon. It is made one atom at a time.

Role in living things

No biological role.

Safety

Only single atoms are ever handled.

Uses

Fundamental research into superheavy element chemistry

Curiosities

  • Rutherfordium was the first element whose chemistry was studied by gas chromatography on single atoms.
  • It behaves like hafnium, which confirmed that the table continues correctly past the actinides.
  • The Soviet name kurchatovium appeared in Russian textbooks until the late 1990s.
  • Ernest Rutherford discovered the atomic nucleus and was the first to transmute one element into another.

Position in the table

Rf