Oxygen bonding orbitals

If only the d orbitals are considered to be important in the bond, the linear dioxo ions have metal orbitals of a, tt and 6 symmetry while the oxygen bonding orbitals have a tt8, and ... 

Figure 11.1 shows the bond dissociation curve at the HF level with the STO-3G, 3-21G, 6-31G(d,p), cc-pVDZ and cc-pVQZ basis sets. The total energy drops considerably upon going from the STO-3G to the 3-21G and again to the 6-3IG(d,p) basis. This is primarily due to the improved description of the oxygen Is-orbital. The two different... 

The carbon-oxygen double bond of a carbonyl group is similar in many respects to the carbon-carbon double bond of an alkene. The carbonyl carbon atom is s/ 2-hybridized and forms three valence electron remains in a carbon p orbital and forms a tt bond to oxygen by overlap with an oxygen p orbital. The oxygen atom also has two nonbonding pairs of electrons, w hich occupy its remaining two orbitals. 

Considering comparable oxygen compounds, predict the shape of H S and H2S2 molecules. What bonding orbitals are used ... 

There are, therefore, three unused d orbitals per ruthenium one of which is used to form a 7r-bond with an unused oxygen p orbital (it has already used the 2s and 2p orbitals in the (7-bonds to the three rutheniums). 

There is (a) cr-donation from a filled oxygen orbital to an empty platinum orbital and (b) 7r back-bonding from a filled metal d orbital into an empty oxygen 7r -anti-bonding orbital. 

In the acetate anion, the two oxygen atoms are equivalent, so we expect that the orbital descriptions about each O atom should be identical. You can verily that they are, and experiments further verily this the two carbon-oxygen bond lengths in acetate are identical. 

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