Rhodium hexafluoride

Rhodium hexafluoride
IUPAC name rhodium(VI) fluoride
Other names rhodium hexafluoride
Identifiers
CAS number	13693-07-7
Jmol-3D images	Image 1
SMILES F[Rh](F)(F)(F)(F)F
InChI InChI=1/6FH.2Rh/h6*1H;;/q;;;;;;+6/p-6
Properties
Molecular formula	F6Rh
Molar mass	216.9 g mol−1
Appearance	black crystalline solid[1]
Density	3.71g/mL[2]
Melting point	≈ 70 °C[1]
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Rhodium hexafluoride, also rhodium(VI) fluoride, (RhF₆) is a compound of rhodium and fluorine and one of the eighteen known binary hexafluorides. It is the most unstable hexafluoride among those of the platinum group elements and it can react with glass even without water.^[3]

Synthesis

Rhodium hexafluoride is made by a direct reaction of rhodium metal with an excess of elemental fluorine gas:^[3]

Description

Rhodium hexafluoride is a black crystalline solid that melts at about 70 °C.^[1] The solid structure measured at −140 °C is orthorhombic space group Pnma. Lattice parameters are a = 9.323 Å, b = 8.474 Å, and c = 4.910 Å. There are four formula units (in this case, discrete molecules) per unit cell, giving a density of 3.71 g·cm⁻³.^[2]

The RhF₆ molecule itself (the form important for the liquid or gas phase) has octahedral molecular geometry, which has point group (O_h). The Rh–F bond length is 1.824 Å.^[2]

References

1. ^ ^{a b c} 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. ^ ^{a b c} 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. ^ ^{a b} (Chinese) 《无机化学丛书》第九卷：锰分族、铁系、铂系. 北京: 科学出版社. p. 478. ISBN 7-03-002238-6. 

Further reading

• Gmelins Handbuch der anorganischen Chemie, System Nr. 63, Rhodium, Part B1, pp. 266–268.

External links

• Rhodium hexafluoride at webelements.com.