The molecular and crystal structures of a homologous series of bipolar, mesogenic biphenyls-HO(CH2)nOC6H4.C6H4CN

The crystal and molecular structures of eight 4,4'-disubstituted biphenyls of the general formula HO-(CH₂)_n-O-C₆H₄-C₆H₄-CN (n=3-5, 7-11) (HnCBPs) have been determined. All compounds investigated have a nearly parallel molecular arrangement in the crystalline state, with dipole-dipole interactions between the molecules. For n≥7, isomorphic layered structures are observed. The inter-molecular packing is different for odd and even numbers of methylene units in the spacer.