Trifluorosilane

Trifluorosilane

Names
IUPAC name Trifluorosilane
Identifiers
CAS Number	13465-71-9  Y
3D model (JSmol)	Interactive image
ChemSpider	122985  Y
PubChem CID	139462
CompTox Dashboard (EPA)	DTXSID70928707
InChI InChI=1S/F3HSi/c1-4(2)3/h4H Y Key: WPPVEXTUHHUEIV-UHFFFAOYSA-N Y InChI=1S/F3HSi/c1-4(2)3/h4H Key: ZDHXKXAHOVTTAH-UHFFFAOYAH
SMILES F[SiH](F)F
Properties
Chemical formula	HF3Si
Molar mass	86.09 g/mol
Appearance	Colorless gas
Density	1.86 g/cm3
Melting point	−131 °C (−204 °F; 142 K)
Boiling point	−97.5 °C (−143.5 °F; 175.7 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Trifluorosilane is the chemical compound with the formula F ₃ H Si. At standard temperature and pressure, trifluorosilane is a colorless gas. ^[1] Note that the free radical F ₃ Si is often also referred to as trifluorosilane, although more properly referred to as trifluorosilyl.

Preparation

Trifluorosilane has been purified and separated by low-temperature high-vacuum distillation. One preparation method involves products of the reaction between SbF₃ and HSiCl₃. ^[2] HSiCl₃ is obtained by copper catalyzed reaction between HCl and Silicon at 200-400 °C.

Formation has also been reported in certain etching operations of silicon. ^[3]

Properties

The electric dipole moment of trifluorosilane is 1.26 debye. ^[4] The length of the silicon to fluorine bond is 1.555 Å, Si-H length is 1.55 Å, and ∠FSiF is 110°. ^[5]

References

1. Perry, Dale L. (2011-06-15). Handbook of Inorganic Compounds, Second Edition. CRC Press. ISBN   9781439814628.
2. Zuckerman, J. J. (2009-09-17). Inorganic Reactions and Methods, The Formation of Bonds to Halogens. John Wiley & Sons. ISBN   9780470145388.
3. Lippold, Marcus; Böhme, Uwe; Gondek, Christoph; Kronstein, Martin; Patzig-Klein, Sebastian; Weser, Martin; Kroke, Edwin (December 2012). "Etching Silicon with HF-HNO ₃ -H ₂ SO ₄ /H ₂ O Mixtures - Unprecedented Formation of Trifluorosilane, Hexafluorodisiloxane, and Si-F Surface Groups" . European Journal of Inorganic Chemistry. 2012 (34): 5714–5721. doi:10.1002/ejic.201200674. ISSN   1434-1948 . Retrieved 2014-08-27.
4. Ghosh, S. N.; Trambarulo, Ralph; Gordy, Walter (February 1953). "Electric Dipole Moments of Several Molecules from the Stark Effect". The Journal of Chemical Physics. 21 (2): 308–310. Bibcode:1953JChPh..21..308G. doi:10.1063/1.1698877.
5. Sheridan, John; Gordy, Walter (1 March 1950). "Microwave Spectra and Molecular Constants of Trifluorosilane Derivatives. Si F 3 H, Si F 3 C H 3, Si F 3 Cl, and Si F 3 Br". Physical Review. 77 (5): 719. Bibcode:1950PhRv...77..719S. doi:10.1103/PhysRev.77.719.

Further reading

• Demaison, J.; Margulès, L.; Breidung, J.; Thiel, W.; Bürger, H. (10 November 1999). "Ab initio anharmonic force field, spectroscopic parameters and equilibrium structure of trifluorosilane". Molecular Physics. 97 (9): 1053–1067. Bibcode:1999MolPh..97.1053D. doi:10.1080/00268979909482906.