Benzene molecular orbital diagram

Fig. 20. (a) One component of the bonding et metal-benzene molecular orbital set. Diagrams (b) and (c) illustrate the effect of tilting the p orbitals of the benzene and cyclopropenyl rings. 

Draw resonance structures and molecular orbital diagrams for benzene and other cyclic conjugated molecules. 

Figure 1.27. Molecular orbital diagram for bis(benzene)chromium.

FIGURE 3.39 The molecular orbital energy-level diagram for the ir-orbitals of benzene. In the ground state of the molecule, only the net bonding orbitals are occupied. 

In the benzene molecule, each carbon atom is sp hybridised and the three half-filled sp hybrid orbitals form a bonds with a hydrogen atom and two neighbouring carbon atoms. This leaves an electron occupying a p orbital on each carbon atom. Each of these p orbitals overlaps slde-on with p orbitals on neighbouring carbon atoms, and a tt molecular orbital Is formed, as shown in the diagram. 

Figure 2.27 Energy diagram molecular orbitals of benzene...

Figure 6.4. Energy-level diagram for the molecular orbitals of benzene evaluated in the Huckel approximation.

Figure 4 Molecular orbital correlation diagram for the ortho addition of benzene to ethene. A plane of symmetry (a) is retained during the transition from benzene plus ethene to bicyclo[4.2.0]octa-2,4-diene.

From the orbital correlation diagram derived by Bryce-Smith [38], it was deduced that the ortho cycloaddition is forbidden from the lowest excited singlet state of benzene and the ground state of ethene. Van der Hart et al. [189] have constructed molecular orbital and state correlation diagrams for the ortho photocycloaddition of benzene to ethene. The molecular orbital correlation diagram differs from that given by Bryce-Smith, because natural correlations have been used. From a topological point of view, it seems less desirable to correlate the tt... 

The energy level diagram and the wavefunctions of the six n molecular orbitals in benzene. 

Energy diagram of the molecular orbitals of benzene. Benzene s six 77 electrons fill the three bonding orbitals, leaving the antibonding orbitals vacant. 

Q Explain how to construct the molecular orbitals of a conjugated cyclic system similar to benzene and cyclobutadiene. Use the polygon rule to draw the energy diagram, and fill in the electrons to show whether a given compound or ion is aromatic or antiaromatic. 

These then are the six Tt molecular orbitals for benzene. We can draw an energy level diagram to represent them. 

Figure 6-28. Contour diagrams of some molecular orbitals of benzene. Computer drawing by Zoltan Varga with Gaussview [29] (a) cr orbitals (b) tt orbitals.

Fig. 9.9 Energy diagram for the tt molecular orbitals of benzene and the regular hexagon analogue.

Fig. 3 Schematic diagram of the canonical MOs of benzene, phenide anion and phenylacetylene. The highest occupied molecular orbital (HOMO) and three lower ones HOMO-1, HOMO-2 and HOMO-3 are shown along with their symmetry representations...

Shown above is the energy-level diagram for the n orbitals of benzene, calculated on the basis of Hiickel molecular orbital theory. According to this theory, the total energy of the six n electrons of ground-state benzene is given by... 

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