Xenon complexes structure

The starting point for the synthesis of xenon compounds is the preparation of xenon difluoride, XeF2, and xenon tetrafluoride, XeF4, by heating a mixture of the elements to 400°C at 6 atm. At higher pressures, fluorination proceeds as far as xenon hexafluoride, XeFfi. All three fluorides are crystalline solids (Fig. 15.27). In the gas phase, all are molecular compounds. Solid xenon hexafluoride, however, is ionic, with a complex structure consisting of XeF< + cations bridged by F anions. 

The compounds (NO)2[PdF6]319 and [XeFs PdFj320 have been reported. A structural determination on the latter compound showed bond lengths of 1.89 A (Pd—F).320 It has been suggested that the xenon complex XePd2Fi0 is in fact an XeF+ salt of [Pd ] -.307... 

Xenon can act as a complex ligand to form M-Xe bonds, especially with gold, which exhibits significant relativistic effects in view of its electronic structure, as discussed in Section 2.4.3. Some gold-xenon complexes have been prepared and characterized, and their structures are shown in Fig. 17.5.7. 

Xanthocobalt—see Cobalt, nitropentaammine-Xenon, pentafluoro-lone electron pair structure, 50 Xenon, trifluoro-structure, 45 Xenon(IV) complexes six-coordinate compounds structure, 53 Xenon hexafluoride geometry, 37 stereochemistry, 74 X-ray diffraction cobalt ammines, 13 configuration, 16 crystal structure, 15 Xylenol orange metallochromic indicator, 557... 

Direct reaction offluorine with xenon at high temperature yields compounds with oxidation numbers of 4-2 (Xep2, thermodynamically stable), 44 (Xep4), and 4-6 (XePe). In the case of XePe, high pressure is required. All three fluorides are crystalline solids. In the gas phase, all are molecular compoimds. Solid xenon hexafluoride is an ionic compound with a complex structure of XePs" cations bridged by P anions. 

We have recently prepared some new and very thermolabile CO- and N2 comPlexes derived from titanocene [1] or decamethyltitanocene [2], and have characterized them by their vibrational spectra. As well as "classical" matrix spectroscopy, we have used spectroscopy in liquid xenon (LXe). The application of chemistry and methodology indicates the decamethylsilicocene structure, which represents the first example of a stable jt-complex of divalent silicon [3]. Reaction with CO or N2 leads to the two title complexes [4] ... 

Duncanson (i) of the molecular orbital bonding concepts of Dewar (2), which he developed to explain the structure of Ag+-olefin complexes, led to the suggestion that ethylene is symmetrically coordinated to the metal. Platinum, atomic number 78, has the electronic configuration of the xenon core (Is 2s 2p 35 3p 3d Z = 54), then... 

The wide variation in structure, ranging from complex steroids to the inert monatomic gas xenon, led to several theories of anesthetic action. The mechanism by which inhalation anesthetics manifest their effect is not exactly known. Since they do not belong to one chemical class of compounds, the correlations between structure and activity are also not known. Inhalation anesthetics are nonspecific and therefore there are not specific antagonists. Interaction of inhalation anesthetics with cellular structures can only be described as van der Waals interactions. There are a number of hypotheses that have been advanced to explain the action of inhalation anesthetics however, none of them can adequately describe the entire spectrum of effects caused by inhalation anesthetics. 

Treatment of the chloro-bridged complex [PdCl(7r-C3H5)]2 with cyclo-pentadienylsodium gives 7r-al lyl-rr-cyclopentadienylpalladiu m (II) [Pd(ir-C3H6)(7r-C6H6)] as dark red, voltatile crystals, mp 64° (190). Its nmr spectrum (191) confirms the sandwich structure (L) in which the palladium has the electronic configuration of xenon. 

Structure of Xenon Tetra-fluoride, 70 Vibronic transitions, 438 Video complex, 388, 491, 493 Vitamin Bl2, and coenzymes, 929-931... 

Vicinal fluoroalkyl ethers are also obtained from olefins and methyl hypo-fluorite at low temperatures [168] and from the unstable reagents generated from additions of xenon difluoride to methanol [169] or other alcohols [170] Alcohols tend to give complex product mixtures depending on the olefin structure, and best results are often achieved when reactions are run in the presence of boron tri-fluonde Additions of xenon difluoride to trifluoromcthanesulfomc fluorosulfonic, or nitric acids give fluoroxenonium reagents that are stable to about -10 °C and... 

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