Lithium hexafluorosilicate

Crystal structure
	__ Li + __ Si 4+ __ F -
Crystal system	trigonal
Space group	P 321 (No. 150)
Lattice parameters	a = 8.219 (2) Å, c = 4.5580 (9) Å, Z = 3
Coordination numbers	[6] Si, [6] Li
General
Surname	Lithium hexafluorosilicate
other names	Lithium hexafluorosilicate; Lithium hexafluoridosilicate;
Ratio formula	Li 2 [SiF 6 ]
Brief description	white odorless solid
External identifiers / databases
EC number	241-372-6
ECHA InfoCard	100,037,595
PubChem	13629069
Wikidata	Q27921277
properties
Molar mass	155.96 g mol −1
Physical state	firmly
density	2.8 g cm −3
Melting point	250 ° C (decomposition)
solubility	soluble in water and methanol
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 302
	P: 264-270-301 + 312-330-501
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Lithium hexafluorosilicate is a chemical compound of lithium from the group of hexafluorosilicates .

Extraction and presentation

Lithium hexafluorosilicate can be obtained by reacting hexafluoridosilicic acid with lithium hydroxide or lithium carbonate or by reacting silicon tetrafluoride with lithium fluoride . It was first synthesized in 1954 by B. Cox.

{\ displaystyle {\ ce {H2 [SiF6] + 2LiOH -> Li2 [SiF6] + 2H2O}}}

properties

Lithium hexafluorosilicate is a white, odorless solid that is soluble in water and methanol. When heated above 250 ° C it decomposes into lithium fluoride and silicon (IV) fluoride and has a trigonal crystal structure with the space group P 321 (space group no. 150) and three formula units per unit cell, isotypic to sodium hexafluorosilicate . Template: room group / 150

use

Lithium hexafluorosilicate is used as an intermediate in the manufacture of pharmaceuticals and other chemical compounds. It is also an intermediate product in the preparation of lithium chloride from lithium-containing minerals by digestion with hexafluoridosilicic acid.

Individual evidence

↑ ^a ^b ^c ^d Hinteregger, Ernst; Sausage, Klaus; Niederwieser, Niklas; Heymann, Gunter; Huppertz, Hubert: Pressure-supported crystal growth and single-crystal structure determination of Li ₂ SiF ₆ . In: Zeitschrift für Kristallographie - Crystalline Materials , 2014, Volume 229, Issue 2, pp. 77–82, doi: 10.1515 / zkri-2013-1622 .
↑ ^a ^b ^c ^d ^e ^f ^g data sheet Lithium hexafluorosilicate from AlfaAesar, accessed on November 25, 2016 ( PDF )(JavaScript required) .
↑ R. Blachnik: Pocket book for chemists and physicists Volume 3: Elements, inorganic compounds and materials, minerals . Springer-Verlag, 2013, ISBN 978-3-642-58842-6 , pp. 542 ( limited preview in Google Book search).
↑ Entry on fluorosilicates. In: Römpp Online . Georg Thieme Verlag, accessed on November 25, 2016.
^ RJ Meyer: Lithium supplementary volume . Springer-Verlag, 2013, ISBN 978-3-662-12268-6 , pp. 519 ( limited preview in Google Book search).

[DOI10.1515/zkri-2013-1622-1] Hinteregger, Ernst; Sausage, Klaus; Niederwieser, Niklas; Heymann, Gunter; Huppertz, Hubert: Pressure-supported crystal growth and single-crystal structure determination of Li ₂ SiF ₆ . In: Zeitschrift für Kristallographie - Crystalline Materials , 2014, Volume 229, Issue 2, pp. 77–82, doi: 10.1515 / zkri-2013-1622 .

[Alfa-2] ↑ ^a ^b ^c ^d ^e ^f ^g data sheet Lithium hexafluorosilicate from AlfaAesar, accessed on November 25, 2016 ( PDF )(JavaScript required) .

[R._Blachnik-3] R. Blachnik: Pocket book for chemists and physicists Volume 3: Elements, inorganic compounds and materials, minerals . Springer-Verlag, 2013, ISBN 978-3-642-58842-6 , pp. 542 ( limited preview in Google Book search).

[RömppOnline-4] Entry on fluorosilicates. In: Römpp Online . Georg Thieme Verlag, accessed on November 25, 2016.

[R._J._Meyer-5] RJ Meyer: Lithium supplementary volume . Springer-Verlag, 2013, ISBN 978-3-662-12268-6 , pp. 519 ( limited preview in Google Book search).