Abstract: Polymers which can be used in p-type materials for organic electronic devices and photovoltaic cells. Compounds, monomers, dimers, trimers, and polymers comprising: Good photovoltaic efficiency and lifetime can be achieved. The R group can provide solubility, environmental stability, and fine tuning of spectroscopic and/or electronic properties. Different polymer microstructures can be prepared which encourage multiple band gaps and broad and strong absorptions. The carbonyl can interact with adjacent thiophene rings to provide backbone with rigidity, induce planarity, and reduce and/or eliminate intramolecular chain twisting defects. Polymers comprising benzodithiophene and/or benzothiadiazole structures can show particularly high performance.