Fluoride matrix isolation studies

III. Matrix Isolation Studies of Transient, Inorganic, Binary Fluoride Species. 246... 

In this review we summarize and attempt to correlate vibrational spectral data amassed from the literature for the main group, inorganic binary fluorides. In addition, a brief review of the matrix-isolation studies of both reactive intermediates and high-temperature fluoride vapor species is included, placing particular emphasis on the interhalogen molecules. 

The area in which matrix isolation is perhaps of greatest value is the stabilization of transient species such as free radicals and high-temperature vapors. Until quite recently, infrared spectroscopy was utilized almost exclusively for the vibrational studies of matrix-isolated species. With the introduction of laser sources and the development of more sensitive, electronic, light detection systems, Raman matrix-isolation studies are now feasible and have recently been applied to a limited number of unstable inorganic fluoride species including the molecules OF (5) and C1F2 (6). Both of these species were formed for Raman study by a novel technique that utilizes the... 

The crystal structures of the three heavier thallium(I) halides have been established and lattice energies calculated the inert pair of T1+ is apparently insignificant in terms of the stability of the lattice. The enthalpy of hydration of the Tl ion was also derived. Gas phase (TlBr, Til) and matrix isolation studies (TlCl, TlBr, Til) have shown that TlX and TI2X2 species are important.Complex formation in aqueous solution decreases in the order Cl > Br > I, and as with the fluorides, the double salts show no evidence of anionic complex formation by Tl Finally, it is important to note that TII3 is formulated as Tr(lT) from X-ray studies.Thermal decomposition yields TI3I4, whose structure has not been reported. 

Jacox, M.E. and Milligan, D.E., Matrix-isolation study of the vacuum-ultraviolet photolysis of methyl fluoride. The infrared spectra of the free radicals CF, HCF and HjCF, /. Chem. Phys., 50, 3252, 1969. 

Many fluorides, particularly the interhalogens, are very reactive and require special handling techniques. Matrix isolation has proven to be a very useful technique in the study of inorganic fluorides it is particularly helpful in the study of very reactive species, such as... 

The salt molecule technique, in conjunction with matrix isolation, appears to be a promising technique for the study of high temperature reactions, and a further development of this approach should be beneficial. Extension to additional ion pair adducts would appear feasible, allowing for the study of unusual fluoride-containing anions. Extension may also be possible to oxide salt vaporization and reaction to forrt oxyanions with a -2 charge in matrix isolated triple anions, but this avenue has only been briefly explored. Perhaps the results obtained to date and described here as well as the numerous studies which could not be mentioned, will stimulate further study, both experimental and theoretical, in this area of high temperature chemistry. 

More recently, the matrix isolation of the linear, centrosymmetric, compounds, HNgX (where Ng = Xe, Kr, Ar and X = halide) has been achieved. A theoretical study reveals that HF hydrogen bonding will be fairly strong to the fluoride of HNgF. ... 

A d.t.a. study has shown that in the temperature range 500—800 C, SF reacts with oxides of Group II and III elements with considerable evolution of heat. The gaseous products were found to be SO2 and sulphuryl fluoride, with thionyl fluoride being observed in the reaction of AI2O3 with SF. The first matrix-isolation and i.r. spectral identification of the SFs radical, as produced by the vacuum-u.v. photolysis of SF and its derivatives, and by controlled attack by fluorine atom on SF4, has been announced. Compounds of the type SF5— N=S(F)NR2 and SF5—N=S(NR2)2 have been prepared by Si—bond-cleavage reactions of silylamines with pentafluorosulphur-sulphur difluoride imide the... 

IR studies of matrix-isolated rare-earth fluorides. Parentheses indicate estimated values. 

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