Phosphorus trifluoride
Phosphorus trifluoride (formula PF3), is a colorless and odorless gas. It is highly toxic and reacts slowly with water. Its main use is as a ligand in metal complexes. As a ligand, it parallels carbon monoxide in metal carbonyls, and indeed its toxicity is due to its binding with the iron in blood hemoglobin in a similar way to carbon monoxide.
Physical properties
Phosphorus trifluoride has a bond angle of 107°, F-P-F bond angle being 96.3°. Gaseous PF3 has a standard enthalpy of formation of -945 kJ/mol (-226 kcal/mol). The phosphorus atom has a nuclear magnetic resonance chemical shift of 97 ppm (downfield of H3PO4).
Properties
Phosphorus trifluoride hydrolyzes especially at high pH, but it is less hydrolytically sensitive than phosphorus trichloride. It does not attack glass except at high temperatures, and anhydrous potassium hydroxide may be used to dry it with little loss. With hot metals, phosphides and fluorides are formed. With Lewis bases such as ammonia addition products (adducts) are formed, and PF3 is oxidized by oxidizing agents such as bromine or potassium permanganate.
Phosphorus trifluoride (data page)
This page provides supplementary chemical data on phosphorus trifluoride.
Structure and properties
Thermodynamic properties
Spectral data
References
Except where noted otherwise, data relate to standard ambient temperature and pressure.
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