Is Glass the Answer
tration—perhaps 5 mole per cent in dis-^ sociated water, and somewhat more in systems richer in oxygen. The existence of these hydrogen polyoxides has significance for chemical valence bond theory, thermodynamics, and reaction kinetics. It has been postulated by some scientists that the polyoxides occur as intermediates in hydrogen-oxygen reactions, combustion, flames, and in pulse radiolysis of aqueous solutions of acids. As members of a homologous series beginning with H 2 0 and H 2 0 2 , they illustrate the reluctant catenation (chain formation) of oxygen, unlike its congener in the periodic table, sulfur, which forms compounds u p to H 2 S 8 . T h e prospects for stabilizing and isolating H 2 0 3 or H 2 0 4 in a bottle are therefore rather poor, says Dr. Giguère.
Raman spectra. The two Quebec scientists, together with Dr. X. Deglise, have also investigated the Raman spectra of the materials, observing a fourth band at 500 c m . - 1 , besides the three bands in the IR spectra. Furthermore, they cannot account for the intensity pattern of the first three bands in terms of H 2 0 3 molecules only. Dr. Giguère therefore concludes that a species besides H 2 0 3 is present, and hypothesizes it to be H 2 0 4 . Chemical bond energy considerations indicate that H 2 0 4 molecules should be too unstable to exist, except at temperatures even lower than liquid nitrogen, but he suggests that extra stabilization in both species—H 2 0 3 and H 2 0 4 —might be provided by hydrogen bonding. At any rate, the higher oxides would exist only in low concen-
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ing carbonyls in [ N i ( ^ C 5 H 5 ) C O ] 2 ,
The oxygen end of a bridging carbonyl group may exhibit basicity toward aluminum alkyls. And this Lewis basicity appears to be a general phenomenon, according to D . F . Shriver and coworkers at Northwestern University, Evanston, 111. Although many compounds are known in which cyanide is coordinated through both carbon and nitrogen, until recently the isoelectric CO ligand had been known to bond only through carbon. Last year, the Northwestern group described the first observation of carbon and oxygen coordinated CO in the compounds [ F e ( ^ C 5 H 5 ) ( C O ) 2 ] 2 • 2A1(C 2 H 5 ) 3 and [ F e ( ^ C 5 H 5 ) C O ] 4 · 4A1(C 2 H 5 ) 3 . Dr. Shriver told the inorganic Chemistry divisions (ACS/CIC) that bridg-
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C 5 H 5 ) ( C O ) 2 ] 2 will also coordinate with aluminum alkyls. Moreover, introduction of an aluminum alkyl to the ruthenium complex induces carbonyl groups to shift from terminal to bridging positions. Dr. Shriver says that his group obtained convincing infrared evidence that addition of triisobutyl aluminum to a ruthenium system (see box) displaced the equilibrium to the right. Presumably, coordination of the triisobutyl aluminum to the bridging CO groups serves as the driving force. Another system which affords an example of induced shifts of CO from terminal to bridging positions in the presence of triisobutyl aluminum is [Mo(7r-C 5 H 5 )(CO) 3 ] 2 , which ordinarily contains terminal CO groups only.
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