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Part II: Recent Progress in Xe(II) and Xe(IV)
Oxide Fluoride Chemistry
University of Oulu, Finland
Main-Group Chemistry Summer School
August 27-31, 2012
Lecture II
2 M. Gerken, B.E. Pointner, M. Moran, G.J. Schrobilgen, H.P.A. Mercier, J.A. Boatz, B. Hoge, K.O. Christe, J. Am. Chem. Soc., 2009, 131, 13474.
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8 M.D. Moran, D. Brock, H.P.A. Mercier, G.J. Schrobilgen, J. Am. Chem. Soc., 2010, 132, 13823.
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10 M.D. Moran, D. Brock, H.P.A. Mercier, G.J. Schrobilgen, J. Am. Chem. Soc., 2010, 132, 13823.
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Synthesis of FXeOClO2
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Synthesis of FXeOClO2
FXeOXeFXeF+ has been used to prepare FXeOClO2 in a reaction
analogous to that used to prepare FXeONO2. •
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NMR Spectra of FXeOClO2
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XeO2
Xenon(IV) Species
n = 0 or 1
XeF4 XeOF2 XeO2 FxXe(OTeF5)4-x O=XeFn(OTeF5)2-n *
XeOF2∙nHF
F2OXeN≡CCH3 F3XeOIOF4
XeF3+ XeOF+ C6F5XeF2
+ Xe(OTeF5)3+ *
HOXeF2+ *
HOXe(F)2OXeF2+ * FXeIIOXeIVF2
+ *
FXeIIOXeIV(F)2OXeIVF2+ *
XeF5¯ XeOF3
¯ XeO2F¯
Unknown. * Not fully characterized.
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17 D.S. Brock, V. Bilir, H.P.A. Mercier, G.J. Schrobilgen J. Am. Chem. Soc. 2007, 129, 3598.
18 D. Brock, H.P.A. Mercier, G.J. Schrobilgen, J. Am. Chem. Soc., 2010, 132, 10935.
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XeOF2·nHF + AsF5 HOXeF2+AsF6
– + (n-1)HF
HOXeF2+AsF6
– XeF+AsF6– + HF + ½O2
HF
1h @ –78 oC
–35 oC
rapid out-gassing
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26 26
XeO2 & Earth’s Missing Xenon
• Studies have shown that as much as 90% of the
Earth’s primordial xenon is absent from its
atmosphere.
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M. Ozima, F. A. Podosek, J. Geophys. Res. 1999, 104, 25493.
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• It has been proposed that xenon displaces silicon from
quartz (SiO2) at the high pressures (0.7−5 GPa) and
temperatures (500−1500 K) that are encountered in the
continental crust.
• A “(Si, Xe)O2 network” was proposed based on X-ray
powder diffraction and Raman spectroscopy
SiO2(quartz) + Xe(s) Si(s) + XeO2(s)
C. Sanloup, B. C. Schmidt, E. M. C. Perrez, A. Jambon, E. Gregoryanz, M. Mezouar,
Science 2005, 310, 1174-1177.
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Known Xenon Oxides
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[Na]4[XeO6] + 2H2SO4 XeO4 + 2[Na]2[SO4] + 2H2O
XeF6 + 3H2O XeO3 + 6HF
4XeF4 + 8H2O 2XeO3 + 2Xe + O2 + 16HF
• An early study reported the hydrolysis of XeF4 and the
formation of a transient yellow-colored solid in pure and
acidified (H2SO4) water at 0 oC. The yellow product was
never isolated or characterized.
H2SO4 (conc.)
D. F. Smith J. Am. Chem. Soc. 1963, 85, 816.
D. H. Templeton, A. Zalkin, J. D. Forrester, S. M. Williamson, J. Am. Chem. Soc. 1963, 85, 817.
H. Selig, H. H. Claassen, C. L. Chernick, J. G. Malm, J. L. Huston, Science 1964, 143, 1322-1323.
E. H. Appelman, J. G. Malm, J. Am. Chem. Soc. 1964, 86, 2141-2148.
S. M. Williamson, C. W. Koch In Noble Gas Compounds; H. H. Hyman, Ed.;
University of Chicago Press: Chicago, 1963, pp 149−151.
pale yellow solid
colorless solid
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• XeF4 was hydrolyzed in excess H2O and the resulting
suspension centrifuged at 0 oC, followed by quenching the
mixture at −78 oC.
XeF4 + 2H2O(excess) XeO2 + 4HF
• The product was characterized by low-temperature Raman
spectroscopy with the use of 1/2H- and 16/18O-isotopic
enrichment. The spectra were consistent with the formation
of XeO2.
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XeO2
0 oC
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XeF4 + 2H2O(excess) XeO2 + 4HF 0 oC
XeF4 crystals
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XeO2
31 Asterisks (*) denote lines arising from the FEP sample tube and † denotes a laser artifact.
18O
16O
32 32 32
XeF4 Xe16O2 Xe16/18O2 Xe18O2
D2d assgnts (L = F, O)
586 n6, n(Eu) 632.3(1) 626.5sh 625.8(1) n(E) nas(XeLt − XeLt)
554 n1, n(A1g) 570.3(100) 550.9(100) 542.6(100) n(A1)
n(B2)
ns(XeL4)
524 n4, n(B2g) nas(XeL2t − XeL2t)
291 n3, n(A2u) 283.9(3) 276.9(2) 270.0(3) n(B2) d(XeL4) o.o.p., umbrella mode
218 n2, n(B1g) 239.1(2)
227.9(4)
231sh
221.3(4)
226.6(2)
216.9(6) n(B1) d(XeL2c + XeL2c)
n.o. n5, n(B2u) n.o. n.o. n.o. n(A2) d(XeL2t) o.o.p. – d(XeL2t) o.o.p.
161 n7, n(Eu) 168.9(13) 165.0(19) 161.1(13) n(E) d(XeL2t) i.p.
99.5(14) 99.3(17) 99.5(15) lattice mode
D.S. Brock, G.J. Schrobilgen, J. Am. Chem. Soc. 2011, 133, 6265–6269.
(D4h)
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