Xenon hexafluoride is a noble gas compound with the formula XeF6. It is one of the three binary fluorides of xenon that have been studied experimentally, the other two being XeF2 and XeF4. All known are exergonic and stable at normal temperatures. XeF6 is the strongest fluorinating agent of the series. It is a colorless solid that readily sublimes into intensely yellow vapors.
Xenon hexafluoride can be prepared by heating of XeF2 at about 300 °C under 6 MPa (60 atmospheres) of fluorine. With NiF2 as catalyst, however, this reaction can proceed at 120 °C even in xenon-fluorine molar ratios as low as 1:5.
The structure of XeF6 required several years to establish in contrast to the cases of XeF2 and XeF4. In the gas phase the compound is monomeric. VSEPR theory predicts that due to the presence of six fluoride ligands and one lone pair of electrons the structure lacks perfect octahedral symmetry, and indeed electron diffraction combined with high-level calculations indicate that the compound's point group is C3v. It is a fluxional molecule. Oh is only insignificantly higher, indicating that the minimum on the energy surface is very shallow.
129Xe and 19F NMR spectroscopy indicates that in solution the compound assumes a tetrameric structure: four equivalent xenon atoms are arranged in a tetrahedron surrounded by a fluctuating array of 24 fluorine atoms that interchange positions in a "cogwheel mechanism".
Six polymorphs of XeF6 are known. including one that contains XeF ions with bridging F ions.
Xenon hexafluoride hydrolyzes, ultimately affording xenon trioxide:
XeF6 + H2O → XeOF4 + 2 HF
XeOF4 + H2O → XeO2F2 + 2 HF
XeO2F2 + H2O → XeO3 + 2 HF
XeF6 + 3 H2O → XeO3 + 6 HF
XeF6 is a Lewis acid, binding one and two fluoride anions:
XeF6 + F− → XeF
XeF + F− → XeF
Salts of the octafluoroxenate(VI) anion (XeF) are very stable, decomposing only above 400 °C. This anion has been shown to have square antiprismatic geometry, based on single-crystal X-ray counter analysis of its nitrosonium salt, (NO)2XeF8.
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
This course will provide an introduction to model category theory, which is an abstract framework for generalizing homotopy theory beyond topological spaces and continuous maps. We will study numerous
A first graduate course in algorithms, this course assumes minimal background, but moves rapidly. The objective is to learn the main techniques of algorithm analysis and design, while building a reper
The course introduces the paradigm of quantum computation in an axiomatic way. We introduce the notion of quantum bit, gates, circuits and we treat the most important quantum algorithms. We also touch
Xenon difluoride is a powerful fluorinating agent with the chemical formula XeF2, and one of the most stable xenon compounds. Like most covalent inorganic fluorides it is moisture-sensitive. It decomposes on contact with water vapor, but is otherwise stable in storage. Xenon difluoride is a dense, colourless crystalline solid. It has a nauseating odour and low vapor pressure. Xenon difluoride is a linear molecule with an Xe–F bond length of 197.73pm in the vapor stage, and 200 pm in the solid phase.
Krypton difluoride, KrF2 is a chemical compound of krypton and fluorine. It was the first compound of krypton discovered. It is a volatile, colourless solid at room temperature. The structure of the KrF2 molecule is linear, with Kr−F distances of 188.9 pm. It reacts with strong Lewis acids to form salts of the KrF+ and KrF3+ cations. The atomization energy of KrF2 (KrF2(g) → Kr(g) + F2(g)) is 21.9 kcal/mol, giving an average Kr–F bond energy of only 11 kcal/mol, the weakest of any isolable fluoride.
Xenon is a chemical element with the symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized. Xenon is used in flash lamps and arc lamps, and as a general anesthetic. The first excimer laser design used a xenon dimer molecule (Xe2) as the lasing medium, and the earliest laser designs used xenon flash lamps as pumps.
High-resolution transmission electron microscopy, electron diffraction, and electron energy-loss spectroscopy provide information on the structural evolution, dielectric function, and bandgap values of nanocrystalline 10nm thick lanthanum doped hafnia (La: ...
The project focuses on etching properties of the atomic layer deposition (ALD) of Al2O3. For this purpose, etching processes such as plasma etch with sulfur hexafluoride (SF6), gas etch with xenon difluoride (XeF2), wet etch with MIF developer (726 MIF) as ...
2023
,
The morphology and structure of damaged regions (tracks) produced by swift heavy 167, 77, and 46 MeV 132Xe23+ ions in YBCO-based second generation industrial high temperature superconductors wires (2G HTS) were studied using transmission electron microscop ...