Structural and optoelectronic properties of phenylene-furan, phenylene-pyrrole and phenylene-thiophene oligomers are reported using density functional theory methods. Studies reveal that stabilities of conformers change with increasing chain length, and helical conformers are energetically feasible for large oligomers of the studied systems, due to stacking interactions between adjacent helical turns. Absorption spectra of helices are dominated by multiple number of electronic transitions other than the S-0 -> S-1, involving orbitals other than the HOMO/LUMO. All studied helices are optically active having similar pattern of negative and positive peaks in the CD spectra. (C) 2017 Elsevier B.V. All rights reserved.