Rhenium hexafluoride

Rhenium hexafluoride, also rhenium(VI) fluoride, (ReF6) is a compound of rhenium and fluorine and one of the seventeen known binary hexafluorides.

Rhenium hexafluoride
Names
IUPAC name
rhenium(VI) fluoride
Other names
rhenium hexafluoride
Identifiers
3D model (JSmol)
ECHA InfoCard 100.030.144
EC Number
  • 233-172-2
UNII
Properties
F6Re
Molar mass 300.20 g/mol
Appearance liquid, or yellow crystalline solid[1]
Density 4.94g/mL[2]
Melting point 18.5 °C (65.3 °F; 291.6 K)[1]
Boiling point 33.7 °C (92.7 °F; 306.8 K)[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Synthesis

Rhenium hexafluoride is made by combining rhenium heptafluoride with additional rhenium metal at 300 °C in a pressure vessel.[2]

6 ReF
7 + Re → 7 ReF
6

Description

Rhenium hexafluoride is a liquid at room temperature. At 18.5 °C, it freezes into a yellow solid. The boiling point is 33.7 °C.[1]

The solid structure measured at −140 °C is orthorhombic space group Pnma. Lattice parameters are a = 9.417 Å, b = 8.570 Å, and c = 4.965 Å. There are four formula units (in this case, discrete molecules) per unit cell, giving a density of 4.94 g·cm−3.[2]

The ReF6 molecule itself (the form important for the liquid or gas phase) has octahedral molecular geometry, which has point group (Oh). The Re–F bond length is 1.823 Å.[2]

Use

Rhenium hexafluoride is a commercial material used in the electronics industry for depositing films of rhenium.[3]

References
  1. CRC Handbook of Chemistry and Physics, 90th Edition, CRC Press, Boca Raton, Florida, 2009, ISBN 978-1-4200-9084-0, Section 4, Physical Constants of Inorganic Compounds, p. 4-85.
  2. T. Drews, J. Supeł, A. Hagenbach, K. Seppelt: "Solid State Molecular Structures of Transition Metal Hexafluorides", in: Inorganic Chemistry, 2006, 45 (9), S. 3782–3788; doi:10.1021/ic052029f; PMID 16634614.
  3. Meshri, D. T. (2000). "Fluorine Compounds, Inorganic, Rhenium". Kirk-Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.1808051413051908.a01. ISBN 0471238961.

Further reading
  • Gmelins Handbuch der anorganischen Chemie, System Nr. 70, Rhenium, Part A, pp. 102–105.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.