Thallium • Other Metal

Primary XPS region: Tl4f
Overlapping regions: Al2s, Bi5p, Ge3p3, Cu3s
Binding energies of common chemical states:

Chemical stateBinding energy Tl4f7/2/eV

Experimental Information


Interpretation of XPS spectra


hexAbout This Element

Symbol: Tl
Date of Discovery: 1861
Name Origin: Greek thallos
Appearance: silvery white
Discoverer: Sir William Crookes
Obtained From: copper, lead, zinc, sulfide ores

Melting Point: 303.5 K
Boiling Point: 1473 K
Density[kg/m3]: 11.85
Molar Volume: 17.22×10-6m3/mol [Xe]4f145d106s26p1
Protons/Electrons: 81
Oxidation State: 3,1
Crystal Structure: Hexagonal
Shell Structure: 2,8,18,32,18,3
Neutrons: 123
Electron Configuration: Xe 4f14 5d10 6s2 6p1

Thallium was discovered spectroscopically in 1861 by Sir William Crookes. Very soft and malleable, thallium can be cut with a knife at room temperature. This element exhibits a metallic luster when freshly exposed to air, but soon becomes bluish-grey, resembling tin or lead. The element and its compounds are toxic and must be handled carefully. Thallium is believed to cause cancer. Thallium-doped silicon is a semiconductor material used in infrared detectors. Thallium bromide-iodide crystals may also be found in infrared detectors. Thallium is used as a rat and ant killer. It was originally used in treating ringworm and other skin infections.

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