Krypton complexes

Krypton complexes may be prepared directly by the reaction of Krp2 with the appropriate binary fluoride, neat or in solution. In some cases, binary fluorides have been prepared in situ using Krp2 as the fluorinating agent. So far, no X-ray crystal structure of any Krp2 complex has been determined, and the characterization of the complexes has rested largely on vibrational spectroscopy. Raman spectroscopy has been especially valuable in studies of these compounds, all of which are of low thermal stability. 

One other system investigated in detail by TRIR is the photolysis of Rh(> -C5Mes)(CO)2 in Kr(l) and Xe(l). Both the TRIR technique with an IR laser and the method with the FTIR spectrometer synchronized to the pump laser pulse have been reported. The photoproducts are assigned as Rh(> -C5Me5)(CO)Ng on the basis of their IR spectra in the carbonyl-stretching [v(CO)] region (a single band at ca. 1945 cm ) and their reactivity toward CO and alkanes. The krypton complex proves to be far more reactive than the xenon complex even at lower temperature. Toward CO, there is a difference in reactivity of a factor of ca. 200 at comparable temperatures ... 

So far krypton has exhibited chemistry only for the +2 oxidation state and only krypton-fluorine compounds are known. All the known divalent krypton complexes consist of molecules which exhibit a significant amount of ionic character and can be described in terms of [KrFl + and [Kr2F3] + containing species. The more complex cation consists of two [KrF]+ units joined by a fluorine bridge. 

Pyrolysis of the krypton complex at between 60 and 65°C gave gold pentafluoride, AuF5 ... 

The investigation [20a] of the photoinitiated reaction of Cp Rh(CO)2 with neopentane in liquid krypton by low-temperature IR flash kinetic spectroscopy gave the results that are consistent with a pre-equilibrium mechanism. According to this mechanism, an initially formed transient krypton complex Cp Rh-(CO)(Kr) is in rapid equilibrium with a transient (uninserted) alkane complex... 

Thallium(I) chloride cm 4.54299 2 Benzene-krypton complex CjHj.Kr 0.136 0.002 58... 

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