POTENTIAL USES OF CARBONYL DIFLUORIDE

There are also potentially important inorganic applications of COF. Most of the industrially important low-oxidation-state metal fluorides are prepared from the reaction of their oxides, hydroxides or carbonates with aqueous or anhydrous HF. However, preparation of fluorides of metals in high formal oxidation states is usually achieved by the use of elemental fluorine on the metal, because of the problem of hydrolysis from the reversible reaction of the oxide with HF  

Indeed, in a recent patent, phosgene was used as a drying agent in this reaction, for the syntheses of niobium(V) fluoride and tantalum(V) fluoride [1481a]. COF can provide a completely anhydrous route to these compounds, generating CO, instead of water as the co-product (see Section 13.13.2)  

It has also been suggested that COF, may be added to CO/O, mixtures to enhance the thermal deburring of superalloys, such as Nimonic 90 and Nimonic 80A [1130]. 

Perhaps the most likely immediate commercial application of carbonyl fluoride, however, arises from its spectroscopic properties. Irradiation of mixtures of COF, and H, (or D,), over a wide pressure range and at ambient temperature, with the multiline output of a continuous wave CO, laser, results in the generation of excited state HF (DF) which lases [1387]. Energy transfer from the R, line (970 cm ) of CO, (which is close in energy to the c, band of COF,) causes the dissociation of the COF, to CO and two excited state fluorine atoms which subsequentiy react with the dihydrogen (or dideuterium). However, COF, itself has been found to effect rapid vibrational de-excitation of HF [239], an observation that suggests that the COF,/H, route to the HF laser may be of limited practicality. 

In related experiments, COF, (formed in situ) has been shown to reduce the output power of DF-CO, transfer chemical lasers [553,611]. These lasers, which achieve population inversion by intermolecular energy transfer to the asymmetric stretching mode of CO, viz. 

---