Molecular orbitals

Molecular orbital

Formed from the combination of atomic orbitals, consists of a bonding and an anti bonding molecular orbital

Shape of molecular orbitals in bonds

symmetrical in non polar molecular bonds, asymmetrical in polar covalent bonds (more electron density around more electronegative atom)

Sp3 hybridisation

The 2s and 2p orbitals combine to form 4 degenerate sp3 orbitals, arranged in a tetrahedral shape.

Sp2 hybridisation

The 2s and two of the 2p orbitals combine to form 3 degenerate sp2 orbitals, leaving one 2p orbital remaining. The sp2 orbitals lie at 90° to the p orbital, and are arranged in a trigonal planar shape.

Sigma bonds

These are covalent bonds formed between atoms during the end-on overlap of atomic orbitals to form a molecular orbital

Pi bonds

These are covalent bonds formed by sideways overlap of two parallel atomic orbitals

Number of bonds in sp2 hybridised carbons

3 sigma bonds and 1 pi bond can be formed.

Number of bonds in sp3 hybridised carbons

4 sigma bonds can be formed

Sp hybridisation