Samarium hexaboride

Crystal structure
	__ Sm 3+ __ B
General
Surname	Samarium hexaboride
Ratio formula	SmB 6
Brief description	blue solid
External identifiers / databases
EC number	234-536-3
ECHA InfoCard	100,031,384
Wikidata	Q7408855
properties
Molar mass	215.22 g mol −1
Physical state	firmly
density	5.07 g cm −3
Melting point	2580 ° C
solubility	practically insoluble in water
safety instructions
GHS labeling of hazardous substances	no GHS pictograms
	no GHS pictograms
H and P phrases	H: no H-phrases
	P: no P-phrases
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Samarium hexaboride is an inorganic chemical compound of samarium and besides SmB ₄ , SmB ₆ and the unstable Sm ₂ B ₅ one of the known samarium borides.

Extraction and presentation

Samarium hexaboride can be obtained by reacting samarium (III) chloride or samarium (III) oxide with boron (III) oxide and magnesium or by reacting samarium (III) oxide / samarium (III) chloride with sodium borohydride .

{\ displaystyle \ mathrm {Sm_ {2} O_ {3} +6 \ B_ {2} O_ {3} +21 \ Mg \ longrightarrow 2 \ SmB_ {6} +21 \ MgO}}

It is also possible to display it by reacting samarium (III) oxide with boron carbide , boron or boron / carbon mixtures at 1000 to 2000 ° C in a vacuum .

properties

Samarium hexaboride is a blue solid that is practically insoluble in water. It has a cubic crystal structure of the cesium chloride type with the space group Pm 3 m (space group no. 221) and is a semiconductor . At low temperatures it is a topological insulator , a Kondo insulator . Template: room group / 221

use

Samarium hexaboride can be used as a control material for nuclear reactors .

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g data sheet Samarium boride, 99.9% from AlfaAesar, accessed on June 18, 2016 ( PDF )(JavaScript required) .
↑ ^a ^b ^c ^d Duygu Ağaoğulları, Özge Balcı, M. Lütfi Öveçoğlu, C. Suryanarayana, İsmail Duman: Synthesis of bulk nanocrystalline samarium hexaboride . In: Journal of the European Ceramic Society . tape 35 , no. 15 , 15 August 2015, ISSN 0955-2219 , p. 4121-4136 , doi : 10.1016 / j.jeurceramsoc.2015.07.037 ( researchgate.net ).
^ Issues in Chemistry and General Chemical Research: 2011 Edition . ScholarlyEditions, 2012, ISBN 1-4649-6329-0 ( limited preview in Google Book Search).
↑ Lihong Bao, Luomeng Chao, Yingjie Li, Ming Ming, B. Yibole, O. Tegus: SmB6 nanoparticles: Synthesis, valence states, and magnetic properties. In: Journal of Alloys and Compounds. 651, 2015, p. 19, doi : 10.1016 / j.jallcom.2015.06.086 .
↑ Prasanta Misra: Heavy-Fermion Systems . Elsevier, 2007, ISBN 978-0-08-055467-9 , pp. 324 ( limited preview in Google Book search).
↑ DJ Kim, J. Xia, Z. Fisk: Topological surface state in the Kondo insulator samarium hexaboride. In: Nature Materials. 13, 2014, p. 466, doi : 10.1038 / nmat3913 .
↑ G. Li, Z. Xiang, F. Yu, T. Asaba, B. Lawson, P. Cai, C. Tinsman, A. Berkley, S. Wolgast, YS Eo, D.-J. Kim, C. Kurdak, JW Allen, K. Sun, XH Chen, YY Wang, Z. Fisk, L. Li: Two-dimensional Fermi surfaces in Kondo insulator SmB6. In: Science. 346, 2014, p. 1208, doi : 10.1126 / science.1250366 .
^ Rainer Pöttgen, Dirk Johrendt: Intermetallics Synthesis, Structure, Function . Walter de Gruyter GmbH & Co KG, 2014, ISBN 978-3-486-85618-7 , p. 72 ( limited preview in Google Book search).

[Alfa-1] ↑ ^a ^b ^c ^d ^e ^f ^g data sheet Samarium boride, 99.9% from AlfaAesar, accessed on June 18, 2016 ( PDF )(JavaScript required) .

[10.1016/j.jeurceramsoc.2015.07.037-2] Duygu Ağaoğulları, Özge Balcı, M. Lütfi Öveçoğlu, C. Suryanarayana, İsmail Duman: Synthesis of bulk nanocrystalline samarium hexaboride . In: Journal of the European Ceramic Society . tape 35 , no. 15 , 15 August 2015, ISSN 0955-2219 , p. 4121-4136 , doi : 10.1016 / j.jeurceramsoc.2015.07.037 ( researchgate.net ).

[3] Issues in Chemistry and General Chemical Research: 2011 Edition . ScholarlyEditions, 2012, ISBN 1-4649-6329-0 ( limited preview in Google Book Search).

[DOI10.1016/j.jallcom.2015.06.086-4] Lihong Bao, Luomeng Chao, Yingjie Li, Ming Ming, B. Yibole, O. Tegus: SmB6 nanoparticles: Synthesis, valence states, and magnetic properties. In: Journal of Alloys and Compounds. 651, 2015, p. 19, doi : 10.1016 / j.jallcom.2015.06.086 .

[Prasanta_Misra-5] Prasanta Misra: Heavy-Fermion Systems . Elsevier, 2007, ISBN 978-0-08-055467-9 , pp. 324 ( limited preview in Google Book search).

[DOI10.1038/nmat3913-6] DJ Kim, J. Xia, Z. Fisk: Topological surface state in the Kondo insulator samarium hexaboride. In: Nature Materials. 13, 2014, p. 466, doi : 10.1038 / nmat3913 .

[DOI10.1126/science.1250366-7] G. Li, Z. Xiang, F. Yu, T. Asaba, B. Lawson, P. Cai, C. Tinsman, A. Berkley, S. Wolgast, YS Eo, D.-J. Kim, C. Kurdak, JW Allen, K. Sun, XH Chen, YY Wang, Z. Fisk, L. Li: Two-dimensional Fermi surfaces in Kondo insulator SmB6. In: Science. 346, 2014, p. 1208, doi : 10.1126 / science.1250366 .

[Rainer_Pöttgen,_Dirk_Johrendt-8] Rainer Pöttgen, Dirk Johrendt: Intermetallics Synthesis, Structure, Function . Walter de Gruyter GmbH & Co KG, 2014, ISBN 978-3-486-85618-7 , p. 72 ( limited preview in Google Book search).