Rhenium (VI) oxide

Crystal structure
	__ Re 6+ __ O 2−
Crystal system	cubic
Space group	Pm 3 m (No. 221)
Lattice parameters	a = 374.8 pm
General
Surname	Rhenium (VI) oxide
other names	Rhenium trioxide
Ratio formula	ReO 3
Brief description	red to purple solid
External identifiers / databases
EC number	215-228-8
ECHA InfoCard	100,013,845
PubChem	102110
Wikidata	Q418954
properties
Molar mass	234.21 g mol −1
Physical state	firmly
density	6.9 g cm −3
Melting point	400 ° C (decomposition)
solubility	almost 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
Thermodynamic properties
ΔH f 0	−605 kJ mol −1
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Rhenium (VI) oxide ReO ₃ is a chemical compound and is one of the oxides of rhenium . It is a red crystalline solid. Rhenium (VI) oxide is known primarily for its crystal structure , which is used as a structure type. Rhenium (VI) oxide is the only stable oxide of the manganese group in the + VI oxidation state .

Extraction and presentation

Rhenium (VI) oxide can be obtained from rhenium (VII) oxide by reduction . The reaction is possible, for example, with carbon monoxide at about 200 ° C or elemental rhenium at 400 ° C.

{\ displaystyle {\ ce {Re2O7 + CO -> 2ReO3 + CO2}}}

{\ displaystyle {\ ce {3Re2O7 + Re -> 7ReO3}}}

Rhenium (VI) oxide can be obtained by reacting rhenium (VII) oxide with dioxane and water with slight heating. The intermediate dioxane complex is decomposed at 145 ° C, whereby the complex initially melts at around 100 ° C to a colorless to blue-green liquid, which after a short time decomposes to red rhenium (VI) oxide and volatile rhenium-free products.

{\ displaystyle {\ ce {Re2O7 + 2H2O + 2C4H8O2 -> Re2O7.2H2O.2C4H8O2}}}

{\ displaystyle {\ ce {Re2O7.2H2O.2C4H8O2 -> 2ReO3 + decomposition products}}}

properties

Rhenium (VI) oxide

Physical Properties

Rhenium (VI) oxide is a moisture-sensitive red, purple-red to purple odorless solid, with a green sheen in transmitted light.

Rhenium (VI) oxide has a characteristic crystal structure that is similar to the perovskite structure. It differs from this only in the lack of a central atom (in perovskite calcium ). Each rhenium atom is surrounded by oxygen atoms in an octahedral manner , while the oxygen atoms are located between two rhenium atoms. It is thus a cubic primitive unit cell with the space group Pm 3 m (space group no. 221) and the lattice parameter a = 374.8 pm. Template: room group / 221

Rhenium (VI) oxide has some metallic properties, so the specific resistance is very low and decreases with falling temperatures. Rhenium (VI) oxide also has a metallic sheen.

Chemical properties

Rhenium (VI) oxide is not soluble in water or in dilute acids and bases . When boiled in hot lye, it disproportionates into ReO ₂ and ReO ₄^- .

It reacts with oxygen at elevated temperatures to form rhenium (VII) oxide. In concentrated nitric acid , reaction takes place to form perrhenic acid . It disproportionates in a vacuum at temperatures above 300 ° C to form rhenium (IV) oxide and rhenium (VII) oxide.

Individual evidence

↑ ^a ^b T.-S. Chang, P. Trucano: Lattice parameters and thermal expansion of ReO ₃ between 291 and 464 K . In: Journal of Applied Crystallography . tape 11 , 1978, p. 286-288 , doi : 10.1107 / S0021889878013333 .
↑ ^a ^b ^c ^d ^e ^f data sheet Rhenium (VI) oxide, 99.9% (metals basis) from AlfaAesar, accessed on December 7, 2019 ( PDF )(JavaScript required) .
^ William M. Haynes: CRC Handbook of Chemistry and Physics . CRC Press, 2016, ISBN 978-1-4987-5429-3 , pp. 98 ( limited preview in Google Book search).
^ AF Holleman , N. Wiberg : Inorganische Chemie . 103rd edition. Volume 2: Subgroup elements, lanthanoids, actinides, transactinides. Walter de Gruyter, Berlin / Boston 2016, ISBN 978-3-11-049590-4 , p. 1921 (Reading sample: Part C - Subgroup elements. Google book search ).
↑ ^a ^b ^c Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1616.
^ Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . Taylor & Francis US, 2011, ISBN 1-4398-1462-7 , pp. 345 ( limited preview in Google Book search).

literature

AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 .
NN Greenwood, A. Earnshaw: Chemistry of the Elements . 1st edition. VCH Verlagsgesellschaft, 1988, ISBN 3-527-26169-9

Web links

Rhenium (VI) oxide at webelements.com

[kristalldaten-1] T.-S. Chang, P. Trucano: Lattice parameters and thermal expansion of ReO ₃ between 291 and 464 K . In: Journal of Applied Crystallography . tape 11 , 1978, p. 286-288 , doi : 10.1107 / S0021889878013333 .

[alfa-2] ↑ ^a ^b ^c ^d ^e ^f data sheet Rhenium (VI) oxide, 99.9% (metals basis) from AlfaAesar, accessed on December 7, 2019 ( PDF )(JavaScript required) .

[William_M._Haynes-3] William M. Haynes: CRC Handbook of Chemistry and Physics . CRC Press, 2016, ISBN 978-1-4987-5429-3 , pp. 98 ( limited preview in Google Book search).

[4] AF Holleman , N. Wiberg : Inorganische Chemie . 103rd edition. Volume 2: Subgroup elements, lanthanoids, actinides, transactinides. Walter de Gruyter, Berlin / Boston 2016, ISBN 978-3-11-049590-4 , p. 1921 (Reading sample: Part C - Subgroup elements. Google book search ).

[brauer-5] Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1616.

[Dale_L._Perry-6] Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . Taylor & Francis US, 2011, ISBN 1-4398-1462-7 , pp. 345 ( limited preview in Google Book search).