Thulium • Lanthanide Rare Earth

Primary XPS region: Tm4d
Overlapping regions: N/A
Binding energies of common chemical states: N/A

Experimental Information


Interpretation of XPS spectra


hexAbout This Element

Symbol: Tm
Date of Discovery: 1879
Name Origin: Thule, Scandinavia
Appearance: silvery white
Discoverer: Per Teodor Cleve
Obtained From: monazite

Melting Point: 1545 K
Boiling Point: 1950 K
Density[kg/m3]: 9.32
Molar Volume: 19.1 × 10-6 m3/mol
Protons/Electrons: 69
Neutrons: 100
Shell Structure: 2,8,18,31,8,2
Electron Configuration: [Xe]4f136s2
Oxidation State: 3
Crystal Structure: Hexagonal

Thulium is a rare earth metal never found in as a free element. It is found in small quantities with other rare earths in minerals such as monazite. In pure form, this metal has a bright, silvery lustre. Thulium is reasonably stable in air, but must be protected from moisture. The element is silvery-grey, soft, malleable, and ductile, and can be cut with a knife. It currently has no commercial applications, although one of its isotopes, thulium-169, could be used as a radiation source for portable X-ray machines. First identified in Sweden by chemist Per Theodor Cleve, Thulium gets its name from the ancient name for Scandinavia, Thule.

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