The benzene molecule is composed of 6 carbon atoms joined in a ring with 1 hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.
Although the compound has been very extensively studied since its first isolation in 1825, its molecular dynamics - especially at temperatures below 77K when it becomes a solid - are extremely complex and its inner mechanics remain mostly unexplored.
Benzene is one of the most prototypical molecules in organic chemistry: it is the elemental unit of all aromatic compounds and the π-bonding of its carbon atoms serves as the quintessential example of electron delocalization. The molecular dynamics of the C6H6 molecule are extremely complex and not yet fully understood"
Source : Indirect observation of molecular disassociation in solid benzene at low temperatures arXiv, 2017