The group has an empirical formula of C3H5 and chemical bonds from each of the three carbons to both of the other two.
Due to the unfavoured bond angles (60°), cyclopropyl groups are highly strained.
Two orbital models were proposed to describe the bonding situation.
Here the two sp-hybrids forming the ring bond are separated into one sp2-hybrid and one pure p-orbital.
Cyclopropyl groups are good donors in hyperconjugation resulting in a considerable stabilization of carbocations.