The Xenon Difluoride Complexes XeF₂ · XeOF₄; XeF₂ · XeF₆ · AsF₅ and XeF₂ · 2 XeF₆ · 2 AsF₅ and Their Relevance to Bond Polarity and Fluoride Ion Donor Ability of XeF₂ and XeF₆

Abstract

Abstract Xenon difluoride forms a 1:1 complex with XeOF 4 (m.p. 29°C) which is isostructural with XeF 2 · IF 5 . The unit cell is tetragonal with a = 7.56(2), c = 11.36(3) Å, V = 647 Å 3 , z = 4. R AMAN data prove it to be a molecular complex, the structure of which is compatible with appreciable bond polarity in XeF 2 . Similar interactions of XeF 2 with the XeF + 5 cation are indicated by the R AMAN spectra of the complexes which XeF 2 forms with [XeF 5 ] + [AsF 6 ] − . The spectrum of the 1:2 complex indicates that the XeF 2 molecule is undistorted but the spectrum of the 1:1 complex suggests that the XeF 2 molecule is distorted by interaction with XeF + 5 ions. The occurrence of molecular XeF 2 in the XeF + 5 AsF 6 lattice confirms the superiority of XeF 6 to XeF 2 as a fluoride ion donor.