71 2 · 8 · 18 · 32 · 9 · 2

Lutetium, Lu, element 71

Lanthanide· Period 6· Group 3· d-block

Configuration [Xe]4f¹⁴5d¹6s²

Atomic weight: 174.967Da
Phase: solid
Density: 9.84g/cm³
Melting point: 1,936.15K 1,663 °C
Boiling point: 3,675.15K 3,402 °C
Electronegativity: 1

Silvery-white rare-earth metal which is relatively stable in air. It happens to be the most expensive rare-earth metal. Its found with almost all rare-earth metals, but is very difficult to separate from other elements. Least abundant of all natural elements. Used in metal alloys, and as a catalyst in various processes. There are two natural, stable isotopes, and seven radioisotopes, the most stable being Lu-174 with a half-life of 3.3 years. The separation of lutetium from Ytterbium was described by Georges Urbain in 1907. It was discovered at approximately the same time by Carl Auer von Welsbach. The name comes from the Greek word lutetia which means Paris. Description from mendeleev.

Back to the table

The outermost shell: the valence electronsThe inner shellsThe nucleus One bead for each electron, on the ring of its shell, counted from the nucleus out. The rings turn at their own pace; the model is Bohr's picture of the atom, which places electrons in shells but not on true orbits.

Atomic properties

5 of 5 fields have a value for lutetium

Atomic weight The standard atomic weight. For an element with no stable isotope, the mass of its longest-lived isotope.: 174.9668Da; Source: mendeleev
Electron configuration: [Xe]4f¹⁴5d¹6s²; Source: mendeleev
Uncertainty of the atomic weight: 1×10⁻⁴Da; Source: mendeleev
Electron configuration in full The electron configuration with the noble-gas core written out.: 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰4f¹⁴5s²5p⁶5d¹6s²; Source: Worked outfrom electron configuration
Electrons in each shell Counted from the electron configuration, from the first shell outward.: 2 · 8 · 18 · 32 · 9 · 2; Source: Worked outfrom electron configuration

Screening of each subshell

Clementi's screening constants: how much of the nucleus's charge the other electrons hide from an electron in each subshell. What is left is the effective nuclear charge it feels.

Subshell	Screening σ	Effective charge Z − σ
1s	1.3805	69.6195
2s	18.5502	52.4498
2p	4.389	66.611
3s	21.4655	49.5345
3p	20.8337	50.1663
3d	13.5812	57.4188
4s	32.7308	38.2692
4p	33.8096	37.1904
4d	35.7108	35.2892
4f	40.0688	30.9312
5s	50.045	20.955
5p	52.32	18.68
5d	50.887	20.113
6s	62.1956	8.8044