Oxygen atomic orbitals

In column I, by convention small letters are representations for electron orbital symmetries and capital letters for molecular symmetries. These four distinct behaviour patterns are called symmetry species. Thus symmetries of oxygen atomic orbitals are... 

The effectiveness of the second type of overlap presumably determines the extent of oMnic character of tho epoxide. That ethylene oxides are less unaaturated in character than the corresponding cyclopropane derivatives is then attributable to a less favorable oxygen atomic-orbital orientation. The Walsh model is a satisfactory one in that it predicts accurately the C—H bond force constants... 

FIGURE 8.8 Orbital overlaps between metal and oxygen atom orbitals to form bonding, nonbonding, and antibonding molecular orbitals. 

An early prediction by El-Sayed [588b] that the halogen atoms should have a negligible influence upon the t —>n phosphorescent lifetimes of these compoimds (relative to COHj) has, in more recent work [337], been refuted. A marked dependence in the predicted lifetimes is revealed in the data in Table 17.14, and this has been attributed [337] to mixing between the halogen and the oxygen atomic orbitals. 

Molecular Symmetry Orbitals Oxygen Atomic Orbitals Group Orbitals from Hydrogen Atoms Description... 

One pair of electrons in eacih of two oxygen atomic orbitals... 

The frontier orbitals are the Ibi, 3ai and the n states. We recognize these orbitals as two Px- and pj,-type oxygen atomic orbitals interacting with symmetric and antisymmetric hydrogen atomic orbital combinations (lb2 and 3ai, resprectively). The Ibi molecular orbital is the non-bonded 2p atomic orbital on oxygen. All three of these states are... 

We can use the character table in a similar fashion to assign vibrations and molecular orbitals. Sticking with H2O we give the examples of the OH symmetric and asymmetric stretches (Figure 2.10) and the 2s and 2p oxygen atomic orbitals (Figure 2.11). 

The angle between the two hydrogen-oxygen bonds is about 105°. This is close to the angle expected for sp hybridization of the oxygen-atom orbitals. 

Hydrogen atomic Molecular 4f IsO Oxygen atomic orbitals (with Molecular Hydrogen atomic... 

Orbital correlation diagram for carbon monoxide. The carbon atomic orbital energies are on the left, and the oxygen atomic orbital energies are on the right. The molecular orbitals that form from mixing of the atomic orbitals are represented by the horizontal lines in the center at their approximate orbital energies in the CO molecule. The vertical lines indicate the orbital occupancy. 

Initially we shall form the bonding and antibonding linear combinations of each pair of nitrogen and oxygen atomic orbitals. The resulting symmetry orbitals are given inEqs. (1) and (2),... 

In the addendum for this chapter, the contribution to antiferromagnetism that arises from the overlap between the nearest-neighbour copper and oxygen atomic orbitals is discussed. 

The additional delocalization of the spin density observed in the planar complexes of Cu(II) and octahedral complexes of Ni(II), is associated with the fact that in these complexes the unpaired electron occupies the d 2 y2 orbital which forms a bonds with the ligands. The overlap of the d 2 2 orbital with nitrogen and oxygen atomic orbitals causes delocalization of the spin density onto these atoms as well. From the coordinating atom spin density is further transferred to the CH3 protons via the system of a bonds. The absence of visible spin density delocalization in the complex of Cr(II) may be explained by the fact that in this case the d 2 y2 orbital has no unpaired electron. 

Fig, 1.28 shows the approximate shapes of the orbitals. Notice that the oxygen atomic orbital contributes more to the bonding orbital than does the carbon atomic orbital, but the reverse is true for the antibonding orbital. 

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