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Astatine

Astatine • Halogen

Primary XPS region: Rn4f
Overlapping regions: La4p, Xe4s
Binding energies of common chemical states:

Chemical state Binding energy I3d5/2/eV
Element 210

Experimental Information

Interpretation of XPS spectra

About This Element

Symbol: At
Date of Discovery: 1940
Name Origin: Greek astatos
Appearance: unknown
Discoverer: D. R. Corson
Obtained From: man-made

Melting Point: 575 K
Boiling Point: 610 K
Density[kg/m3]: N/A
Molar Volume: N/A
Protons/Electrons: 85
Neutrons: 125
Shell Structure: 2,8,18,32,18,7
Electron Configuration: [Xe]4f145d106s26p5
Oxidation State: ±1,3,5,7 (unknown)
Crystal Structure: N/A

Astatine is the heaviest of the halogens and is essentially unavailable in nature with less than one teaspoon of the element found in the Earth’s crust at any one time. In 1940, D. R. Corson, K.R. MacKenzie, and Emilio Segre of the University of California, Berkeley discovered that the only possible way of producing astatine is by bombarding bismuth with energetic alpha particles. Similar to the metallic element iodine, astatine accumulates in the thyroid gland.

 



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