• Aromatic molecules?consist of one or more rings with?conjugated?π systems
• Conjugated π systems?arise from alternating double and single bonds in which the electrons are?delocalised
• Aromatic compounds are called ‘aromatic’ as they often have pleasant odours

?Examples of aromatic compounds including benzene table

Shape of benzene & aromatic compounds

• Benzene and other aromatic compounds contain sp²?hybridised carbons as?two?of their?p?orbitals have mixed with an s orbital
• This means that each carbon atom in benzene and other aromatic compounds has?one p orbital

The carbon atoms in aromatic compounds are sp^2?hybridized as two of their p orbitals mix with an s orbital

• Each carbon atom in the ring forms three σ bonds using the sp²?orbitals
• The remaining?p orbital?overlaps laterally with p orbitals of neighbouring carbon atoms to form a π bond
• This extensive sideways overlap of p orbitals results in the electrons being delocalised and able to freely spread over the entire ring
• Benzene and other aromatic compounds are?regular?and?planar?compounds with bond angles of 120^o
• The delocalisation of electrons means that all of the carbon-carbon bonds in these compounds are identical and have both?single?and?double bond?character
• The bonds all being the same length is evidence for the delocalised ring structure of benzene

Like other aromatic compounds, benzene has a planar structure due to the sp²?hybridisation of carbon atoms and the conjugated π system in the ring