Manipulation of the electronic and photovoltaic properties of materials based on small push-pull molecules by substitution of the arylamine donor block by aliphatic groups

•Small push-pull molecules based on triphenylamine have been synthesized.•The effects of replacing a phenyl ring of TPA by aliphatic chains is analyzed.•Aliphatic chains have minor effect on the energy levels of the molecule.•Aliphatic groups can strongly affect the structure and properties of the materials.

Push-pull molecules with an arylamine donor block connected to a dicyanovinyl acceptor via a thienyl π-conjugating spacer have been synthesized in order to analyze the effects of replacing an outer phenyl ring of the triphenylamine (TPA) block of a reference compound by methyl, hexyl, heptafluoropentyl and dioxaoctyl groups. Optical, electrochemical and X-ray diffraction data show that these substitutions have minor influence on the energy levels of the molecule but exert a considerable effect on the structure, optical, electrical and photovoltaic properties of the resulting materials.

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