Raman study of molecular dynamics of inorganic fluoroxidizers in nonaqueous solutions Part 4. Xenon tetrafluoride and xenon hexafluoride in hydrogen fluoride

Raman spectra of XeF4 and XeF6 in the nonaqueous HF solutions at various co ncentrations and vibrational spectra of the [XeF5](+) cation in the solid s tate and in the HF solutions over a wide range of vibrational frequencies h ave been studied. The assignments of the observed vibrational bands of the [XeF5](+) cation and XeF6-HF system has been made. A number of associates o r solvates being formed as a result of the donor-acceptor interaction betwe en Lewis base and Lewis acid has been shown to exist alongside with ionized monomeric and polymeric modifications of XeF6 in the HF solution such as ( [XeF5]F-+(-))(n) (n = 1, 2, 4). The contours of the nu(1)(A(1g)) band of Xe F4 with frequency 552 cm(-1) and bands of stretching modes of ([XeF5]F-+(-) )(n) (n = 1, 2, 4) with frequency in the range of 600-670 cm(-1) are analys ed. The correlation functions of the vibrational and rotational relaxation as well as the corresponding characteristic time for these processes have b een calculated. A conclusion has been driven at that it is vibrational deph asing that makes the major contribution to the formation of ([XeF5]F+)(4) a nd ([XeF5]F-+(-))(2) band contours, while in the case of [XeF5]F-+(-) and X eF4 the contributions of vibrational dephasing and rotational relaxation ne arly coincide. (C) 2000 Elsevier Science B.V. All rights reserved.