Oxygen molecular structure

Acyl-, 4-alkoxycarbonyl- and 4-phenylazo-pyrazolin-5-ones present the possibility of a fourth tautomer with an exocyclic double bond and a chelated structure. The molecular structure of (138) has been determined by X-ray crystallography (Table 5). It was shown that the hydroxy group participates in an intramolecular hydrogen bond with the carbonyl oxygen atom of the ethoxycarbonyl group at position 4 (8OCSCII21). On the other hand, the fourth isomer is the most stable in 4-phenylazopyrazolones (139), a chelated phenyl-hydrazone structure. 

Figure 4.11 Molecular structures of typical crown-ether complexes with alkali metal cations (a) sodium-water-benzo-I5-crown-5 showing pentagonal-pyramidal coordination of Na by 6 oxygen atoms (b) 18-crown-6-potassium-ethyl acetoacetate enolate showing unsymmelrical coordination of K by 8 oxygen atoms and (c) the RbNCS ion pair coordinated by dibenzo-I8-crown-6 to give seven-fold coordination about Rb.

Figure 5.4 The molecular structure of basic beryllium acetate showing (a) the regular tetrahedral arrangement of 4 Be about the central oxygen and the octahedral arrangement of the 6 bridging acetate groups, and (b) the detailed dimensions of one of the six non-planar 6-membeted heterocycles. (The Be atoms are 24 pm above and below the plane of the acetate group.) The 2 oxygen atoms in each acetate group are equivalent. The central Be-O distances (166.6 pm) are very close to that in BeO itself (165 pm).

Trends in acid strength can be explained in terms of molecular structure. In an oxoacid molecule, the hydrogen atom that dissociates is bonded to oxygen, which in turn is bonded to a nonmetal atom, X. The ionization in water of an oxoacid H—O—X can be represented as... 

Oxychlorides are less prolific, apart from the red-brown OsOCl4 (m.p. 32°C). This probably has a molecular structure in the solid state as the IR spectra of the solid, matrix-isolated and gas-phase molecules are very similar, and the volatility is consonant with this [30]. Syntheses include heating osmium in a stream of oxygen/chlorine ( oxychlorination ) and by ... 

C.5 In the following ball-and-stick molecular structures, black indicates carbon, red oxygen, light gray hydrogen, blue nitrogen, and green chlorine. Write the chemical formula of each structure. 

FIGURE 5 Molecular structures of poly(Bisphenol A carbonate) and poly(Bisphenol A iminocarbonate). The poly(iminocarbonates) are, in a formal sense, derived from polycarbonates by replacement of the carbonyl oxygen by an imino group. 

Chemical characterization of CTx has been difficult because of its very low concentration in fishes (1-20 ppb). The full molecular structure has not yet been elucidated. Data obtained at this time indicate that it is a polar, highly oxygenated... 

Figure 3. The molecular structure of the oxygen tripod ligand [Cp 3Cr3(jX3-0)(p2-OH)3) Q ...

FIGURE 24.1 Molecular structures of common fuel oxygenates. (Adapted from U.S. EPA, Technologies for Treating MTBE and Other Fuel Oxygenates, EPA 542-R-04-009, United States Environmental Protection Agency, Washington, DC, May 2004.)... 

Figure 2 Molecular structure of the trinuclear zinc complex formed with 3-methylcytosinc. All ligands are monodentate and bonding through either a nitrogen or exocyclic oxygen is observed.178...

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