Thorium disilicide

Crystal structure
__ Th      __ Si
General
Surname	Thorium disilicide
other names	Thorium silicide
Ratio formula	ThSi 2
Brief description	black solid
External identifiers / databases
CAS number 12067-54-8 EC number 235-079-2 ECHA InfoCard 100,031,878 PubChem 6336980 Wikidata Q32391749
properties
Molar mass	288.21 g mol −1
Physical state	firmly
density	7.78 g cm −3 (theoretically 8.9 g cm −3 )
Melting point	> 1700 ° C
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Thorium disilicide is an inorganic chemical compound made from thorium and silicon . The connection was first described in detail in 1942 by Georg Brauer and A. Mitius. In addition to this compound, trithorium disilicide , thorium monosilicide , trithorium pentasilicide and Th ₆ Si ₁₁ are further thorium silicides.

Extraction and presentation

Thorium disilicide was obtained in 1905 by reacting thorium dioxide with silicon in an electric arc and in 1907 by Otto Hönigschmid from the elements at 1000 ° C in the presence of aluminum as a solvent .

properties

Thorium disilicide is a black solid. It has a hexagonal crystal structure with the space group P 6 / mmm (space group no. 191) of the aluminum diboride type . There is also a high-temperature form that arises from the low-temperature form from 1300 ° C. This has a tetragonal crystal structure with the space group I 4 ₁ / amd (space group no. 141) .

Individual evidence

1. ^ ^{A b} Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . CRC Press, 2016, ISBN 978-1-4398-1462-8 , pp. 427 ( limited preview in Google Book search).
2. ↑ ^{a b c d} Michael Bickel, Horst Wedemeyer: Th Thorium Supplement Volume C 8 Compounds with Si, P, As, Sb, Bi, and Ge . Springer Science & Business Media, 2013, ISBN 978-3-662-06348-4 , pp. 21 ( limited preview in Google Book search).
3. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
4. ↑ ^{a b} A. BROWN, JJ NORREYS: Beta Polymorphs of Uranium and Thorium Disilicides. In: Nature. 183, 1959, p. 673, doi : 10.1038 / 183673a0 .
5. ↑ G. Brauer, A. Mittius: The crystal structure of the thorium silicide ThSi ₂ . In: Journal of Inorganic and General Chemistry. 249, 1942, p. 325, doi : 10.1002 / zaac.19422490401 .
6. ↑ S. Yagoubi, S. Heathman, A. Svane, G. Vaitheeswaran, P. Heines, J.-C. Griveau, T. Le Bihan, M. Idiri, F. Wastin, R. Caciuffo: High pressure studies on uranium and thorium silicide compounds: Experiment and theory. In: Journal of Alloys and Compounds. 546, 2013, p. 63, doi : 10.1016 / j.jallcom.2012.07.094 .