Sigma antibonding molecular orbitals

For p orbitals, the process is more complex because they can interact with each other in two different ways. For example, two 2p orbitals can approach each other end-to-end to produce a sigma bonding and a sigma antibonding molecular orbital, as shown in Figure 10.24(a). Alternatively, the two p orbitals can... 

If the two atomic orbitals are s-orbitals then the resulting molecular orbitals are called o (sigma) bonding molecular orbitals and a (sigma star) antibonding molecular orbitals (Figure 1.5). 

Sigma (s) Orbital A molecular orbital which is symmetrical about a line joining the two nuclei (the bond axis) is called a sigma (s) orbital. It may be bonding or antibonding molecular orbital. 

Pi bonding and antibonding molecular orbitals. The sideways overlap of two p orbitals leads to a 77 bonding MO and a 77 antibonding MO. A pi bond is not as strong as most sigma bonds. 

Fig. 32 Formation of sigma bonding- and antibonding molecular orbitals from end-to-end...

Define the following terms bonding molecular orbital, antibonding molecular orbital, pi molecular orbital, sigma molecular orbital. 

In forming the N2 from N2, an electron is removed from the sigma bonding molecular orbital. Consequently, the bond order decreases to 2.5 from 3.0. In forming the OJ ion from O2, an electron is removed from the pi antibonding molecular orbital. Consequently, the bond order increases to 2.5 from 2.0. 

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